Tag Archives: Firefox

My FOSDEM 2014

I’m back home after FOSDEM 2014.Lots of coffee A big THANK YOU from me to the organizers of this fine and totally free happening.

Europe’s (the World’s?) biggest open source conference felt even bigger and more crowded this year. There seemed to be more talks that got full, longer lines for food and a worse parking situation.

Nothing of that caused any major concern for me though. I had a great weekend and I met up with a whole busload of friends from all over. Many of them I only meet at FOSDEM. This year I had some additional bonuses by for example meeting up with long-term committers Steve and Dan from the curl project whom I had never met before IRL. Old buddies from Haxx and Rockbox are kind of default! 🙂

Talk-wise this year was also extra good. I’ve always had a soft spot for the Embedded room but this year there was fierce competition for my attention so I spread my time among many rooms and got to see stuff about: clang the compiler, lots of really cool stuff on GDB, valgrind and helgrind, power efficient software, using the GPU to accelerate libreoffice, car automation and open source, how to run Android on low-memory devices, Firefox on Android and more.

I missed out the kdbus talks since it took place in one of them smaller devrooms even though it was “celebrity warning” all over it with Lennart Poettering. In general there’s sometimes this problem at FOSDEM that devrooms have very varying degrees of popularity on the different talks so the size of the room may be too large or too small depending on the separate topics and speakers. But yeah, I understand it is a very hard problem to improve for the organizers.

As a newbie Firefox developer at Mozilla I find it fun to first hear the Firefox on Android talk for an overview on how things  run on that platform now and then I also got references to Firefox both in the helgrind talk and the low-memory Android talk. In both negative and positive senses.

As always on FOSDEM some talks are not super good and we get unprepared speakers who talk quietly, monotone and uninspired but then there’s the awesome people that in spite of accents and the problem of speaking in English as your non-native language, can deliver inspiring and enticing talks that make me just want to immediately run home and try out new things.

The picture on the right is a small tribute to the drinks we could consume to get our spirits up during a talk we perhaps didn’t find the most interesting…

This year I found the helgrind and the gdb-valgrind talks to be especially good together with Meeks’ talk on using the GPU for libreoffice. We generally found that the wifi setup was better than ever before and worked basically all the time.

Accordingly, there were 8333 unique MAC addresses used on the network through the two days, which we then can use to guesstimate the number of attendees. Quite possibly upwards 6000…

See you at FOSDEM 2015. I think I’ll set myself up to talk about something then. I didn’t do any this year.

I go Mozilla

Mozilla dinosaur head logo

In January 2014, I start working for Mozilla

I’ve worked in open source projects for some 20 years and I’ve maintained curl and libcurl for over 15 years. I’m an internet protocol geek at heart and Mozilla seems like a perfect place for me to continue to explore this interest of mine and combine it with real open source in its purest form.

I plan to use my experiences from all my years of protocol fiddling and making stuff work on different platforms against random server implementations into the networking team at Mozilla and work on improving Firefox and more.

I’m putting my current embedded Linux focus to the side and I plunge into a worldwide known company with worldwide known brands to do open source within the internet protocols I enjoy so much. I’ll be working out of my home, just outside Stockholm Sweden. Mozilla has no office in my country and I have no immediate plans of moving anywhere (with a family, kids and all established here).

I intend to bring my mindset on protocols and how to do things well into the Mozilla networking stack and world and I hope and expect that I will get inspiration and input from Mozilla and take that back and further improve curl over time. My agreement with Mozilla also gives me a perfect opportunity to increase my commitment to curl and curl development. I want to maintain and possibly increase my involvement in IETF and the httpbis work with http2 and related stuff. With one foot in Firefox and one in curl going forward, I think I may have a somewhat unique position and attitude toward especially HTTP.

I’ve not yet met another Swedish Mozillian but I know I’m not the only one located in Sweden. I guess I now have a reason to look them up and say hello when suitable.

Björn and Linus will continue to drive and run Haxx with me taking a step back into the shadows (Haxx-wise). I’ll still be part of the collective Haxx just as I was for many years before I started working full-time for Haxx in 2009. My email address, my sites etc will remain on haxx.se.

I’m looking forward to 2014!

The curl year 2012


So what did happen in the curl project during 2012?

First some basic stats

We shipped 6 releases with 199 identified bug fixes and some 40 other changes. That makes on average 33 bug fixes shipped every 61st day or a little over one bug fix done every second day. All this done with about 1000 commits to the git repository, which is roughly the same amount of git activity as 2010 and 2011. We merged commits from 72 different authors, which is a slight increase from the 62 in 2010 and 68 in 2011.

On our main development mailing list, the curl-library list, we now have 1300 subscribers and during 2012 it got about 3500 postings from almost 500 different From addresses. To no surprise, I posted by far the largest amount of mails there (847) with the number two poster being Günter Knauf who posted 151 times. Four more members posted more than 100 times: Steve Holme (145), Dan Fandrich (131), Marc Hoersken (130) and Yang Tse (107). Last year I sent 1175 mails to the same list…

Notable events

I’ve walked through the biggest changes and fixes and here are the particular ones I found stood out during this otherwise rather calm and laid back curl year. Possibly in a rough order of importance…

  1. We started the year with two security vulnerability announcements, regarding an SSL weakness and an injection flaw. They were reported in 2011 though and we didn’t get any further security alerts during 2012 which I think is good. Or a sign that nobody has been looking close enough…
  2. We got two interesting additions in the SSL backend department almost simultaneously. We got native Windows support with the use of the schannel subsystem and we got native Mac OS X support with the use of Darwin SSL. Thanks to these, we can now offer SSL-enabled libcurls on those operating systems without relying on third party SSL libraries.
  3. The VERIFYHOST debacle took off with “security researchers” throwing accusations and insults, ending with us releasing a curl release with the bug removed. It did however unfortunately lead to some follow-up problems in for example the PHP binding.
  4. During the autumn, the brokeness of WSApoll was identified, and we now build libcurl without it and as a result libcurl now works better on Windows!
  5. In an attempt to allow libcurl-using applications to avoid select() and its problems, we introduced the new public function curl_multi_wait. It avoids the FD_SETSIZE limit and makes it harder to screw up…
  6. The overly bloated User-Agent string for the curl tool was dramatically shortened when we cut out all the subsystems/libraries and their version numbers from the string. Now there’s only curl and its version number left. Nice and clean.
  7. In July we finally introduced metalink support in the curl tool with the curl 7.27.0 release. It’s been one of those things we’ve discussed for ages that finally came through and became reality.
  8. With the brand new HTTP CONNECT support in the test suite we suddenly could get much improved test cases that does SSL or just tunnel through an HTTP proxy with the CONNECT request. It of course helps us avoid regressions and otherwise improve curl and libcurl.

What didn’t happen

  1. I made an attempt to get the spindly hacking going, but I’ve mostly failed with that effort. I have personally not had enough time and energy to work on it, and the interest from the rest of the world seems luke warm at best.
  2. HTTP pipelining. Linus Nielsen Feltzing has a patch series in the works with a much improved pipelining support for libcurl. I’ll write a separate post about it once it gets in. Obviously we failed to merge it before the end of the year.
  3. Some of my friends like to mock me about curl not being completely IPv6 friendly due to its lack of support for Happy Eyeballs, and of course they’re right. Making curl just do two connects on IPv6-enabled machines should be a fairly small change but yet I haven’t yet managed to get into actually implementing it…
  4. DANE is SSL cert verification with records from DNS thanks to DNSSEC. Firefox has some experiments going and Chrome already supports it. This is a technology that truly can improve HTTPS going forwards and allow us to avoid the annoyingly weak and broken CA model…

I won’t promise that any of these will happen during 2013 but I can promise there will be efforts…

The Future

I wrote a separate post a short while ago about the HTTP2 progress, and I expect 2013 to bring much more details and discussions in that area. Will we get SRV record support soon? Or perhaps even URI records? Will some of the recent discussions about new HTTP auth schemes develop into something that will reach the internet in the coming year?

In libcurl we will switch to an internal design that is purely non-blocking with a lot of if-then-that-else source code removed for checks which interface that is used. I’ll make a follow-up post with details about that as well as soon as it actually happens.

Our Responsibility

curl and libcurl are considered pillars in the internet world by now. This year I’ve heard from several places by independent sources how people consider support by curl to be an important driver for internet technology. As long as we don’t have it, it hasn’t really reached everyone and that things won’t get adopted for real in the Internet community until curl has it supported. As father of the project it makes me proud and humble, but I also feel the responsibility of making sure that we continue to do the right thing the right way.

I also realize that this position of ours is not automatically glued to us, we need to keep up the good stuff to make it stick.



Google Chrome BallA few weeks ago I decided to give Chrome a good ride on my main machine, a Debian Linux unstable. I use it a lot, every day, and I of course use my browser during a large portion of my time in front of it. I’m a long time Firefox fan and when I’ve heard and read other people converting I’ve always thought it’d be hard for me due to my heavy use of certain plugins, old habits and so on.

(Of course, in Debian lingo the browsers are actually called Chromium and Iceweasel, but I’ve decided to ignore that fact in this post.)

Here’s the story on how it went, what’s good with Chrome and what’s lacking in comparison to Firefox. As compared on my Linux box here.

Obvious benefints:

  • Less wasted window/screen estate. The tabs up in the window title is brilliant.
  • Faster. It’s generally faster in almost every aspect, but what’s most noticeable is when starting it.
  • Less memory hungy. At times I’ve found my Firefox installation to spend an annoying amount of my precious RAM (I have 4GB installed) and even though I would expect Chrome’s a process-per-tab concept to be more expensive memory wise, I’ve had less such problems with it.
  • The unified address/search bar, back to how Firefox once had it, is only sensible.
  • In my Firefox I’ve had two minor quirks for a while that have annoyed me: 1) when I start to search for something, I get a few seconds “freeze” immediately after I’ve started searching. Like I enter a few letters, waaaaaaait, then I can continue. This is certainly nothing life-threatening or something I can’t live through but it is annoying. 2) I occasionally get problems with flash video playbacks that the video pause or studder, most often a few seconds into it. Chrome has not given me these quirks.
  • Mailman! I administrate more than 20 mailing lists on the same host (cool.haxx.se) using mailman. Each list has iFirefox Ballts own URL and its own password. But Firefox just cannot remember them separately!!! These are pages I visit several times each day to ack or reject posts etc. Chrome remembers the passwords excellently for all the individual lists. This makes me a much happier person.

Problems I didn’t get:

  • The adblock version for Chrome is as good. I’m not sure exactly how well they compare but I haven’t noticed anything that’s given me reason to get annoyed.
  • The resizeable text edit areas in Chrome is excellent and removes the need for some of the fancier edit plugins in Firefox.

Things still nicer in Firefox:

  • I love the plugin to force unknown content-types to still be displayed by the browser. Far too many resources are still done using the wrong one and Chrome’s only option is to save it locally and then force me to run a local tool to display the file. Sure, it works fine but when I want to do that on many files it gets tedious.
  • In general Chrome, is a bit worse at handing content it doesn’t know about. I’ve managed to fiddle with my /etc/mozpluggerrc so that at least PDFs are now saved instead of saying “missing plug-in” but so far I’ve failed to get evince to display them directly. Even if it still is possible to make it happen, it is certainly a bit quirky to have to manually edit a text file to make it happen…


I’ll be running Chrome here now for a while!

Testing 2-digit year numbers in cookies

In the current work of the IETF http-state working group, we’re documenting how cookies work. The question came up how browsers and clients treat years in ‘expires’ strings if the year is only specified with two digits. And more precisely, is 69 in the future or in the past?

I decided to figure that out. I setup a little CGI that can be used to check what your browser thinks:


It sends a single cookie header that looks like:

Set-Cookie: testme=yesyes; expires=Wed Sep  1 22:01:55 69;

The CGI script looks like this:

print "Content-Type: text/plain\n";
print "Set-Cookie: testme=yesyes; expires=Wed Sep  1 22:01:55 69;\n";
print "\nempty?\n";
print $ENV{'HTTP_COOKIE'};

You see that it prints the Cookie: header, so if you reload that URL you should see “testme=yesyes” being output if the cookie is still there. If the cookie is still there, your browser of choice treats the date above as a date in the future.

So, what browsers think 69 is in the future and what think 69 is in the past? Feel free to try out more browsers and tell me the results, this is the list we have so far:


Firefox v3 and v4 (year 2069)
curl (year 2038)
IE 7 (year 2069)
Opera (year 2036)
Konqueror 4.5


Chrome (both v4 and v5)
Gnome Epiphany-Webkit

Thanks to my friends in #rockbox-community that helped me out!

(this info was originally posted to the httpstate mailing list)

Beyond just “69”

(this section was added after my first post)

After having done the above basic tests, I proceeded and wrote a slightly more involved test that sets 100 cookies in this format:

Set-Cookie: test$yy=set; expires=Wed Oct  1 22:01:55 $yy;

When the user reloads this page, the page prints all “test$yy” cookies that get sent to the server. The results with the various browsers is very interesting. These are the ranges different browsers think are future:

  • Firefox: 21 – 69 (Safari and Fennec and MicroB on n900) [*]
  • Chrome: 10 – 68
  • Konqueror: 00 – 99 (and IE3, Links, Netsurf, Voyager)
  • curl: 10 – 70
  • Opera: 41 – 69 (and Opera Mobile) [*]
  • IE8: 31 – 79 (and slimbrowser)
  • IE4: 61 – 79 (and IE5, IE6)
  • Midori: 10 – 69 (and IBrowse)
  • w3m: 10 – 37
  • AWeb: 10 – 77
  • Nokia 6300: [none]

[*] = Firefox has a default limit of 50 cookies per host which is the explanation to this funny range. When I changed the config ‘network.cookie.maxPerHost’ to 200 instead (thanks to Dan Witte), I got the more sensible and expected range 10 – 69. Opera has the similar thing, it has a limit of 30 cookies by default which explains the 41-69 limit in this case. It would otherwise get 10-69 as well. (thanks to Stanislaw Adrabinski). I guess that the IE8 range is similarly restricted due to it using a limit of 50 cookies per host and an epoch at 1980.

I couldn’t help myself from trying to parse what this means. The ranges can roughly be summarized like this:

0-9: mostly in the past
10-20: almost always in the future except Firefox
21-30: even more likely to be in the future except IE8
31-37: everyone but opera thinks this is the future
38-40: now w3m and opera think this is the past
41-68: everyone but w3m thinks this is the future
69: Chrome and w3m say past
70: curl, IE8, Konqueror say future
71-79: IE8 and Konqueror say future, everyone else say past
80-99: Konqueror say future, everyone else say past

How to test a browser near you:

  1. goto http://daniel.haxx.se/cookie2.cgi
  2. reload once
  3. the numbers shown on the screen is the year numbers the browsers consider
    to be the future as described above

Java apps froze my Iceweasel

I’ve noticed for quite some time that java apps haven’t seemed to work on my computer when I try to use them with my browser. Whenever I’ve started most java apps, my entire browser has just frozen and gone completely unresponsive and I’ve been forced to kill and restart it.

I run Debian Linux on just about all my machines so of course I do that on my primary desktop as well. And Iceweasel is my browser.

I’ve not really bothered much about the problem as java applets are a bit of yesterday’s technology and I rarely face anything in java that I need. Until today, when I had to login to a customer’s site and use an applet for some work related to my job. There was no decent way to avoid it (apart from perhaps logging in using another machine/browser or similar), so I decided to bite the bullet and finally fix my issue.

I searched around and I tried uninstalling all openjdk stuff and more. I restarted Iceweasel countless times to no avail.

Finally I stumbled over this post by user “almatic” and voila, it fixed my problem. As I just wasted like an hour on this, I’ll help out to make the world a little better by providing the answer here as well:

open file /etc/sysctl.d/bindv6only.conf and set net.ipv6.bindv6only=0, then restart the procfs with invoke-rc.d procps restart

here are the corresponding bugs


SSL certs crash without trust

Eddy Nigg found out and blogged about how he could buy SSL certificates for a domain he clearly doesn’t own nor control. The cert is certified by Comodo who apparently has outsourced (parts of) there cert business to a separate company who obviously does very little or perhaps no verification at all of the buyers.

As a result, buyers could buy certificates from there for just about any domain/site name, and Comodo being a trusted CA in at least Firefox would thus make it a lot easier for phishers and other cyber-style criminals to setup fraudulent sites that even get the padlock in Firefox and looks almost perfectly legitimate!

The question is now what Mozilla should do. What Firefox users should expect their browser to do when HTTPS sites use Comodo-verified certs and how Comodo and their resellers are going to deal with everything…

Read the scary thread on the mozilla dev-tech-crypto list.

Update: if you’re on the paranoid/safe side you can disable trusting their certificates by doing this:

Select Preferences -> Advanced -> View Certificates -> Authorities. Search for
AddTrust AB -> AddTrust External CA Root and click “Edit”. Remove all Flags.

My Firefox Add-ons

I simply need to have this list somewhere so that I can find out my own add-ons again when I’m running Firefox away from home!

Adblock Plus – since ads are too annoying these days

DownThemAll – because I like to be able to get whole batches of images or similar at times

Fission – just a silly eye-candy thing

Forecastfox – I like weather forecasts!

FoxClocks – helps me keep track of the time my friends around the world have at different moments.

It’s All Text – makes web based editing/posting a more pleasurable experience by allowing me to edit such contents with emacs!

Live HTTP Headers is a must when you want to figure out how to repeat your browser’s actions with a set of curl commands.

Open in Browser allows me to open more stuff within the browser itself, even when the Content-Type is bad.

Right-Click-Link is great when you quickly want to browse to links you find in plain text sections.

Torbutton lets me quickly switch to anonymous browsing.

User Agent Switcher lets me trick stupid server-side scripts into beleiving I use a different browser or even operating system.

What great add-ons did I miss?

(Some nitpickers would say that I don’t run Firefox since I use Debian and then it is called Iceweasel, but while that is entirely true, Iceweasel is still the Firefox source code and the Add-ons are in fact still Firefox Add-ons even if they also run perfectly fine on Iceweasel.)

In the middle there is a man

The other day an interesting bug report was posted against the Firefox browser, and it caused some interesting discussions and blog posts on the subject of Man-In-The-Middle attacks and how current browsers etc make it (too?) easy to accept self-signed certificates and thus users are easily mislead. (Peter Burkholder wrote a great piece on SSL MITMing already back in 2002 which goes into detail on how this can be done.).

The entire issue essentially boils down to this:

To be able to really know that you’re communicating with the true remote site (and not an impostor), you must have some kind of verification system.

In SSL land we have this system with CA certs for verifying certs and it works pretty good in most cases (I think). However, so many sites on the internet use HTTPS today without having the certificate signed by a party that is known to the browser already – most of them are so called self-signed which means there’s nobody else that guarantees that they are who they claim to be, just themselves.

All current modern browsers want to give the users easy access to HTTP sites, to HTTPS sites with valid properly-signed certs but also allow users to connect to and browse on HTTPS sites with self-signed certs. And here comes the problem: how to tell users that HTTPS with self-signed certs is very insecure but still let them proceed? How do we tell them that the user may proceed but if this is a known popular site you really should expect a true and valid certificate as otherwise it is quite possibly a MITM you’re seeing?

People are so used to just accept exceptions and click away nagging pop-ups so the warnings and alerts that are explicit and implied by the prompts you have to go through to accept the self-signed certificate. They don’t seem to have much effect. As can be seen in this bug report, accepting an impostor’s certificate for a large known site is far too easy.

In the SSH land however, we don’t have the ca cert system and top-down trust hierarchy that SSL/TLS imposes. But does this matter? I’d say no, as most if not all users still don’t reflect much over the fact when a server’s host key is reported different than what you used before. Or when you connect to a host the first time you accept the host key without trying to verify it using a different channel. Thus you’re subject to pretty much the same MITM risk. The difference is perhaps that less “mere end users” are using SSH this way.

Let me just put emphasis on this: SSL and SSH are secure. The insecureness here is not due to how the protocols work, but rather they are flaws that appear when we mix in real world users and UIs and so.

I don’t have any sensible solutions to these problems myself. I’m crap at designing things for mere humans and UIs etc and I make no claims of understanding end users.

It seems there’s a nice tool called ettercap that’s supposedly a fine thing to use when you want to run your own MITM attacks on your LAN! And on the other side: an interesting take at improving the “accept this certificate” UI is offered by the Firefox’s Perspectives plugin which basically also checks with N other sources’ view to help you decide whether to trust a certificate.

I want to round off my rant with a little quote:

I have little, and decreasing, desire to continue to invest in strong security for a product that discards that security for the masses” [*] / Nelson B Bolyard – prominent NSS hacker

Download (Yester)Day

I won’t be joining the attempted world record of Firefox downloads on the release day June 17th 2008 since I dist-upgraded my Debian unstable just a few days ago and I got my Firef… eh Iceweasel version 3 then.

Of course, others have also noted that Firefox will miss a few Linux users downloading that version as Linux users all over will prefer to get it using their distros’ ordinary means of getting packages and updates…

Firefox 3