Tuesday, September 26, 2017

TenFourFox FPR3 available ... when SourceForge is (also: Fx57 is yugly)

Sorry, everyone. I am well aware that SourceForge is down and you can't download TenFourFox FPR3 (or, for that matter, Classilla) right now. I don't have any control over that. If this keeps up more than a day or two, we'll see if we can get alternative hosting up somewhere.

Also, my office PC (Windows 7) is now on the Firefox 57 beta and it's ... really garish and ugly looking. Switching the layout to Compact and the theme to Light helps a little with the tab bar, but the KITT loading tab animation is distracting, the icons manage to be intrusive and bland simultaneously, and the new logo is a bad LSD trip (to say nothing of the fact half my extensions stopped working, and while I knew that was coming, most of them have no replacement because the APIs don't yet exist). While I thought Australis was a step backwards in terms of utility, at least it had some design consistency. Photon, on the other hand, is all over the place and it's an unwelcome change on top of everything else. I'm almost afraid to update Firefox on the MacBook Air.

But, to be fair, it is palpably faster. Much faster. I certainly can't argue that. Nevertheless, the compromises made are such that if it weren't for Google's relentless commitment to snoop on everything I do, I have to candidly say I'm not sure I'd be sticking with the new Firefox.

Sunday, September 24, 2017

TenFourFox FPR3 available

TenFourFox Feature Parity Release 3 is now available (downloads, hashes, release notes), after much delay due to Floodgap's gateway crapping its pants on Friday night. You'll be interested to know that it's a PowerPC too, by the way (a Motorola Freescale e300 series microcontroller, roughly equivalent to a 603e). There's a reason I have an SLA, which is to have a tech dispatched to Floodgap HQ in the dead of night to reflash the firmware which is specific to my ISP, but it also meant I spent Friday evening twiddling my thumbs instead of applying security patches. Sorry about that.

The fix for issue 72 did not stick, unfortunately, so I backed it out and replaced it with additional debugging code (thus, there is also a Debug version). Other than completing the rest of the relevant security updates, there are no other changes relative to the FPR3 beta. As usual expect this to go live tomorrow night sometime Pacific.

For FPR4, I have another large AltiVec upgrade in mind, and I would like to take a first pass at CSS Grid support and maybe also WOFF2 updates. In addition, because of the impending release of Firefox 57 "Judgment Day for XUL" this will be the first release of TenFourFox to have the "Get Add-ons" tab removed, since the Mozilla-specific pages will be hawking WebExtensions. You can still install old-style XUL addons compatible with the underlying Gecko 45 infrastructure; they'll just be something you have to separately download from AMO or whatever. While I might reintroduce this tab in the future, right now I don't have enough time to maintain a full-service legacy add-on site myself. However, if this is something Someone(tm) wants to work on and they can meet the technical requirements (and make a commitment to hosting it for an indefinite period), we can talk about it and see if you're the right fit for our community. Open a ticket on Github if you're that person.

Friday, September 22, 2017

JAEUA (Just another endangered Universal application), or, the three heads of Tutti II

On this blog, Universal doesn't mean that watered-down 32-bit/64-bit Intel nonsense. It means actually running on multiple system architectures, like 68K and PowerPC in the "fat binary" days, or PowerPC and Intel at the dawn of the OS X i386 era (as OS X has always been able to do even when Marklar was a skunkworks project thanks to NeXTSTEP).

So here's another one. I maintain an emulator of the first home computer I ever had as a kid, the Tomy Tutor, called Tutti II (the original Tutti was actually a simulator for the Commodore 64, and I wrote that too). It descends from an earlier emulator written for Windows called TutorEm which was conveniently SDL-based, so I made some endian fixes for PowerPC and ported it to OS X with some fixes and new features. Download it and play with the demo tape images on the page. It runs on any Mac that can run 10.4 or later, PowerPC or Intel. It runs just dandy on my Sierra-based i7 MacBook Air all the way down to my Tiger-based Sawtooth G4.

The point of this blog post isn't (merely) shameless self-promotion, though; there are some technical points I want to make too. Tutti II isn't just a Universal PowerPC/Intel app; it's actually a three-headed chimera. While the SDL dylib it uses is a relatively pedestrian ppc and i386 Universal library, if you run lipo on the core tutti executable itself you'll find three architectures: one for ppc750 (i.e., G3), one for ppc7400 (i.e., G4), and one for i386 (Intel 32-bit).

Why are there three versions? Because AltiVec. If you look at the source code, you'll find conditional defines for AltiVec acceleration mostly within the TMS 9918A video chip emulation which are used for bitmap splats and scales. This is part of what enables it to run well even on my 1GHz iMac G4. In fact, given that the Mach-O field for number of architectures is a 32-bit integer, you are likely to run out of file offset space (also a 32-bit integer) in a multi-architecture binary long before you run out of actual and artificial architectures to cram in it. Mac OS X looks at the binary and if your system has Intel, runs the Intel portion. If it's PowerPC and it has AltiVec, it runs the AltiVec version, and failing that, the G3 version. No runtime checking is required within the code itself. (The only reason I haven't bothered to do a ppc7450 or ppc970 version too and make it five-headed is because it runs so fast already they're not likely to yield much, if any, noticeable benefit.)

The second point is that this is made much easier because everything is 32-bit. Although Tutti II is mostly Cocoa-based internally and probably could be made to build 64-bit, Xcode 2.5 doesn't support 64-bit Intel compilation, the Universal 10.4 SDK is only 32-bit, and the specific 32-bit SDL 1.2.14 version I use occupies a narrow sweet spot where it uses CoreGraphics instead of QuickDraw for forward compatibility while still functioning on PowerPC 10.4. But, because it's 32-bit, I can build the entire app from the G5 on 10.4 with that library and everything easily descends from almost exactly the same code base. This may no longer be possible after macOS 10.14, whatever it's called (I'm hoping for "macOS Arvin"), ends the ability to run "32-bit applications without compromise." Apple doesn't say what that compromise might be, but my guess is either that the operating system will not include 32-bit components and they will be a separate download for some transitional period (like Rosetta in 10.6), or Intel Carbon applications will be entirely unsupported, as there is no 64-bit Carbon, or maybe even both. Apple may also choose to completely remove things like Intel QuickDraw at the same time, which hasn't been supported since 10.4 but does still run on current versions of macOS, and is only really meaningful for Carbon also. After these pieces are completely decommissioned, you'll have to run High Sierra or Snow Leopard in a VM, I suppose.

As I've mentioned before, this is bad for Power Macs because other than PowerPC bigots like me, what residual PowerPC application support remains is largely due to the fact it works without additional effort and it's more work to remove it than not to bother. I suspect many cross-builders have some old Power Mac or early Intel Mac in a corner with an Xcode that just happens to still build for PowerPC, and the binary it spits out still "just works" on modern Macs, so they leave it alone. Even codesigning didn't really change this much because these cross-platform builders don't like paying the Apple developer tax as much as I don't, so they don't need it (Tutti II is also not a signed application, and probably never will be). Once this is no longer possible, however, these builders will probably just remove PowerPC support entirely since it won't be compatible with newer versions of Xcode, so start preserving source code archives where you find them so you can maintain and build it yourself.

In my case, since I'm planning to move to POWER9 on Linux instead of whatever the next Mac Pro turns out to be, when 32-bit Mac apps are gone completely that will mean the end of Tutti II on current versions of macOS. There will still be a build for Power Macs, but since I'm actually looking into cross-compiling it for Windows, rather than chugging out a special 64-bit macOS build and maintaining it separately I'll just make current Mac users run the 32-bit Windows binary in WINE. That's just less work for me and satisfies my internal curmudgeon, so there.

Look for TenFourFox FPR3 final probably tomorrow or Sunday, depending on when the build cycle finishes.

Tuesday, September 12, 2017

BlueBorne and the Power Mac TL;DR: low practical risk, but assume the worst

Person of Interest, which is one of my favourite shows (Can. You. Hear. Me?) was so very ahead of its time in many respects, and awfully prescient about a lot else. One of those things was taking control of a device for spying purposes via Bluetooth, which the show variously called "forced pairing" or "bluejacking."

Because, thanks to a newly discovered constellation of flaws nicknamed BlueBorne, you can do this for real. Depending on the context and the flaw in question, which varies from operating system to operating system, you can achieve anything from information leaks and man-in-the-middle attacks to full remote code execution without the victim system having to do anything other than merely having their Bluetooth radio on. (And people wonder why I never have Bluetooth enabled on any of my devices and use a wired headset with my phone.)

What versions of OS X are likely vulnerable? The site doesn't say, but it gives us a couple clues with iOS, which shares the XNU kernel. Versions 9.3.5 and prior are all vulnerable to remote code execution, including AppleTV version 7.2.2 which is based on iOS 8.4.2; this correlates with a XNU kernel version of 15.6.0, i.e., El Capitan. Even if we consider there may be some hardening in contemporary desktop versions of macOS, 10.4 and 10.5 are indisputably too old for that, and 10.6 very likely as well. It is therefore reasonable to conclude Power Macs are vulnerable.

As a practical matter, though, an exploit that relies on remote code execution would have to put PowerPC code somewhere it could execute, i.e., the exploit would have to be specific to Power Macs. Unless your neighbour is, well, me, this is probably not a high probability in practice. A bigger risk might be system instability if an OS X exploit is developed and weaponized and tries spraying x86 code at victim systems instead. On a 10.6 system you'd be at real risk of being pwned (more on that below). On a PowerBook G4, they wouldn't be able to take your system over, but it has a good chance of getting bounced up and down and maybe something damaged in the process. This is clearly a greater risk for laptops than desktop systems, since laptops might be in more uncontrolled environments where they could be silently probed by an unobserved attacker.

The solution is obvious: don't leave Bluetooth on, and if you must use it, enable it only in controlled environments. (This would be a good time to look into a wired keyboard or a non-Bluetooth wireless mouse.) My desktop daily drivers, an iMac G4 and my trusty Quad G5, don't have built-in Bluetooth. When I need to push photos from my Pixel, I plug in a USB Bluetooth dongle and physically disconnect it when I'm done. As far as my portable Power Macs in the field, I previously used Bluetooth PAN with my iBook G4 for tethering but I think I'll be switching to WiFi for that even though it uses more power, and leave Bluetooth disabled except if I have no other options. I already use a non-Bluetooth wireless mouse that does not require drivers, so that's covered as well.

Older Intel Mac users, it goes without saying that if you're on anything prior to Sierra you should assume the worst as well. Apple may or may not offer patches for 10.10 and 10.11, but they definitely won't patch 10.9 and earlier, and you are at much greater risk of being successfully exploited than Power Mac users. Don't turn on Bluetooth unless you have to.

Very Soon Now(tm) I will be doing an update to our old post on keeping Power Macs safe online, and this advice will be part of it. Watch for that a little later.

Meanwhile, however, the actual risk to our Power Macs isn't the biggest question this discovery poses. The biggest question is, if the show got this right, what if there's really some sort of Samaritan out there too?

Sunday, September 10, 2017

Irma's silver lining: text is suddenly cool again

In Gopherspace (proxy link if your browser doesn't support it), plain text with low bandwidth was always cool and that's how we underground denizens roll. But as our thoughts and prayers go to the residents of the Caribbean and Florida peninsula being lashed by Hurricane Irma, our obey your media thought overlords newspapers and websites are suddenly realizing that when the crap hits the oscillating storm system, low-bandwidth text is still a pretty good idea.

Introducing text-only CNN. Yes, it's really from CNN. Yes, they really did it. It loads lickety-split in any browser, including TenFourFox and Classilla. And if you're hunkered down in the storm cellar and the radio's playing static and all you can get is an iffy 2G signal from some half-damaged cell tower miles away, this might be your best bet to stay current.

Not to be outdone, there's a Thin National Public Radio site too, though it only seems to have quick summaries instead of full articles.

I hope CNN keeps this running after Irma has passed because we really do need less crap overhead on the web, and in any disaster where communications are impacted, low-bandwidth solutions are the best way to communicate the most information to the most people. Meanwhile, please donate to the American Red Cross and the Salvation Army (or your relief charity of choice) to help the victims of Hurricanes Harvey and Irma today.

Tuesday, September 5, 2017

TenFourFox FPR3b1 available

TenFourFox Feature Parity Release 3 beta 1 is now available (hashes, downloads, release notes). This release has two major updates: first, a whole lot more of the browser has AltiVec in it. All of the relevant call sites that use the slower OS X memory search function memchr() were either converted to the VMX-accelerated version that we introduced for JavaScript in FPR2, or, if the code simply checks to see if a character is there but doesn't need to know where it is, our VMX-accelerated haschr(). This occurs in lots of places, including event handling, font validation and even the network stack; not all of them are hot, but all of them benefit.

The second major change is additional JavaScript ES6 and ES7 compatibility. It's not sufficient for us simply to copy over later versions of JavaScript from browser versions between 45 and 52; besides the fact they may require platform support we don't implement, they don't have our JIT, our PowerPC-specific optimizations and our later updates which would need to be backported and merged, they don't have our accumulated security patches, and they don't have some of the legacy features we need to continue to support 45-era add-ons (particularly legacy generator and array comprehensions). This hybrid engine maintains backwards compatibility but has expanded syntax that fixes some issues with Dropbox (though we still have a couple other glitches to smoke out), Amazon Music and Beta for Pnut, and probably a number of other sites. There is a limit to how much I can cram into the engine and there is a very large frontend refactor around Fx51 which will probably not be easily backported, but there should be more improvements I can squeeze in.

There was also supposed to be a new feature for delaying video decoding until the rest of the page had loaded to improve throughput on YouTube and some other sites, but YouTube introduced its new site design while I was testing the feature, and unfortunately the "lazy loading" technique they appear to be using now means the browser cannot deterministically compute when video will start competing with layout for resources. I'm thinking of a way to retool this but it will not be an enabled part of FPR3. One idea is to forge dropped frames into MSE's statistics early so it shifts to a lower quality stream for a period of time as a "fast start;" another might be to decouple the media state machine from the decoder more completely. I haven't decided how I will attack this problem yet.

In miscellaneous changes, even after desperate begging Imgur would not fix their site sniffer to stop giving us a mobile version using the default TenFourFox user agent (this never used to happen until recently, btw), even if just an image by itself were requested. I got sick of being strung along by their tech support tickets, so this version just doesn't send any user agent to any Imgur site, unless you explicitly select something other than the default. Take that, Imgur. The reason I decided to do this for Imgur specifically is because their mobile site actually causes bugs in TenFourFox due to a hard CoreGraphics limit I can't seem to get around, so serving us the mobile site inappropriately is actually detrimental as opposed to merely annoying. Other miscellaneous changes include some widget tune-ups, more removal of 10.7+ specific code, and responsiveness tweaks to the context menu and awesome bar.

Last but not least, this release has a speculative fix for long-running issue 72 where 10.5 systems could end up with a frozen top menu bar after cycling repeatedly through pop-up menus. You'll notice this does not appear in the source commits yet because I intend to back it out immediately if it doesn't fix the problem (it has a small performance impact even on 10.4 where this issue does not occur). If you are affected by this issue and the optimized build doesn't fix your problem, please report logging to the Github issue from the debug version when the issue triggers. If it does fix it, however, I will commit the patch to the public repo and it will become a part of the widget library.

Other than that, look for the final release on or about September 26. Post questions, concerns and feedback in the comments.