Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

How Apple hides new functionality in iOS: isYoMamaWearsCombatBootsActive

github.com

Post reply on HN
Print view View original

91–100 of 122 posts

Re: How Apple hides new functionality in iOS: isYoMamaWearsCombatBootsActive

#91

Post by mikeash »

andyhmltn wrote: post #29
frank_boyd wrote: post #27

I'd be interested to see the "easter eggs" that drain the battery within 12 hours.

12 hours is a good battery life is it not? Admittedly, the iOS7 BETAs have cut my own down to the point where I have to make sure my phone is on 100% before a 4-5 hour night out so I know I'll have battery to use it by the end of the night. Although I suspect that'll be fixed post-beta

12 hours would be pretty bad for me. My 4S purchased on launch day (so nearly two years old now) gets unplugged at about 8AM, stays unplugged all day, and usually gets plugged in at 11PM with ~50% battery remaining.

Re: How Apple hides new functionality in iOS: isYoMamaWearsCombatBootsActive

#92

Post by cpeterso »

BeOS had is_computer_on() and is_computer_on_fire() APIs:

  int32 is_computer_on(void)

  Returns 1 if the computer is on. If the computer isn't on, the value returned
  by this function is undefined.

  double is_computer_on_fire(void)

  Returns the temperature of the motherboard if the computer is currently on
  fire. If the computer isn't on fire, the function returns some other value.
http://www.tycomsystems.com/beos/bebook/the%20kernel%20kit/s...

Re: How Apple hides new functionality in iOS: isYoMamaWearsCombatBootsActive

#93

Post by spartango »

0x0 wrote: post #24
nwh wrote: post #17

Earlier quoted context omitted.

There's been balmy little bits of stuff like this all the way through OSX and iOS for ages, though maybe not quite as flippant. Every Mac has the kernel extension "Dont Steal Mac OS X.kext" for example, which loads into RAM a short poem. There once was was a user that whined his existing OS was so blind, he'd do better to pirate an OS that ran great but found his hardware declined. Please don't steal Mac OS! Really,…

That .kext is also responsible for verifying some sort of signature in a hardware chip only present on genuine macs. See http://en.wikipedia.org/wiki/Apple%E2%80%93Intel_architectur...

This used to be the case, but no longer is; Apple stopped using the TPM in Intel macs shortly after they launched[1] and have not brought it back since.

DSMOS.kext has another function, however; it is involved in Apple's binary protection scheme[2] for certain OSX binaries. Essentially, OSX ships with certain important binaries (such as loginwindow, SystemUIServer, Finder, and Dock) that have certain vm pages encrypted. Decrypting these pages for use requires DSMOS.kext.

[1]: http://osxbook.com/book/bonus/chapter10/tpm/ [2]: http://www.osxbook.com/book/bonus/chapter7/binaryprotection/

Re: How Apple hides new functionality in iOS: isYoMamaWearsCombatBootsActive

#94

Post by spartango »

pcwalton wrote: post #74
derefr wrote: post #51

Earlier quoted context omitted.

What are protected binaries? This is something I've not heard of OSX having. As far as I know, as long as all the hardware is stuff OSX has drivers for (and you generate a DSDT to describe that hardware) then you don't need any special "authorization." You just put in the OSX installer USB/DVD and it works.

Certain apps, such as the Finder and the SystemUIServer, are encrypted and this kernel extension will only decrypt the executable pages if it considers your Mac to be genuine (consulting the TPM, I believe).

The TPM was used briefly at the beginning of the Intel mac days, but hasn't been used since. The decryption is now done through dsmos.kext in software.

http://osxbook.com/book/bonus/chapter10/tpm/

Re: How Apple hides new functionality in iOS: isYoMamaWearsCombatBootsActive

#95

Post by icebraining »

nwh wrote: post #89
icebraining wrote: post #85

Earlier quoted context omitted.

I don't get the whining either; I was just dispelling a myth. That said, I don't find your arguments compelling; there's a difference between supporting and just not artificially preventing the software from running, and I don't see how doing the latter would make OSX stop "just working" on officially supported machines. In fact, it's not like they don't anyway, and I don't see how have Hackintoshes diluted the exper…

If Apple sold it as an operating system, they'd have to deal with a nightmare of drivers. As it stands one disk can cover almost every Mac ever made, and they're content with that.

Sure, but they wouldn't have to sell it as an operating system just to remove the artificial restrictions. They could still support only their machines, and just not encrypt the binaries and all that nonsense.

But I'm not saying they should, as I said, I don't really care. I'm just saying that just because they don't want to support other machines, that doesn't mean they have to purposely block them.

I mean, Asus doesn't support Linux on their motherboards either, but they don't have BIOS checks verifying that the OS is supported and refusing to boot if it isn't; they just tell you "you're on your own".

Re: How Apple hides new functionality in iOS: isYoMamaWearsCombatBootsActive

#96

Post by breakall »

ultimoo wrote: post #9

I wonder whether Apple will decide to change their strategy of aggressively guarding upcoming products before they are launched, under Cook's leadership. I was following a couple of 'rumor' blogs prior to the iPhone launches earlier this week and I believe they had managed to 'leak' and publish details on the iPhone 5C and 5S pretty spot on. EDIT: rather than referring to the variable names in the OP, I'm referring t…

I wondered the same thing, especially after Phil Schiller's comment: "a few of you probably saw some shots on the Web...and that's cool!"

Re: How Apple hides new functionality in iOS: isYoMamaWearsCombatBootsActive

#97

Post by 0x0 »

spartango wrote: post #93
0x0 wrote: post #24

Earlier quoted context omitted.

That .kext is also responsible for verifying some sort of signature in a hardware chip only present on genuine macs. See http://en.wikipedia.org/wiki/Apple%E2%80%93Intel_architectur...

This used to be the case, but no longer is; Apple stopped using the TPM in Intel macs shortly after they launched[1] and have not brought it back since. DSMOS.kext has another function, however; it is involved in Apple's binary protection scheme[2] for certain OSX binaries. Essentially, OSX ships with certain important binaries (such as loginwindow, SystemUIServer, Finder, and Dock) that have certain vm pages encrypt…

Yes, and before it will perform the decryption, it needs the correct "SmcDeviceKey", so I think my point still stands :)

Re: How Apple hides new functionality in iOS: isYoMamaWearsCombatBootsActive

#98

Post by russellsprouts »

DominikR wrote: post #25
dermatthias wrote: post #14

Earlier quoted context omitted.

Not to forget the gravity constants of the Death Star and The Island, defined by the SensorMananger. http://developer.android.com/reference/android/hardware/Sens... http://developer.android.com/reference/android/hardware/Sens...

I wonder if they seriously discussed internally that gravity constants for other planets were needed in case Android devices would be used in space travel.

Well, there are several on the ISS.

Re: How Apple hides new functionality in iOS: isYoMamaWearsCombatBootsActive

#99

Post by spartango »

derefr wrote: post #51
icebraining wrote: post #44

Earlier quoted context omitted.

Sure, no license key, except for the key used to decrypt protected binaries only on authorized hardware. There is a license "key", it's the whole computer.

What are protected binaries? This is something I've not heard of OSX having. As far as I know, as long as all the hardware is stuff OSX has drivers for (and you generate a DSDT to describe that hardware) then you don't need any special "authorization." You just put in the OSX installer USB/DVD and it works.

OSX does have 'protected binaries', which refers to binaries that use encrypted pages[1] that require decryption via an anti-piracy kernel extension (Don't Steal Mac OS.kext). This extension can check that you're running on Apple hardware by checking with the System Management Controller(SMC), which is Mac-specific[2].

In the old days (10.4), hackintosh systems would patch the protected binaries to remove the page encryption/decryption. Over time kernel extensions were developed to replace the functionality of Don't Steal Mac OS.kext (dsmos.kext or AppleDecrypt.kext) without the hardware checks.

The reason you no longer need either of these extensions is because a kernel extension called FakeSMC.kext was developed, which emulates as much of the functionality of the SMC as possible. This includes thermal and fan monitoring as well as the decryption key storage.

In a modern hackintosh setup, you make use of EFI emulation (inc. DSDT support) included in the bootloader (a boot-132 derivative, most likely Chameleon) and the pre-boot loading of emulator kernel extensions like FakeSMC.kext.

[1]: http://www.osxbook.com/book/bonus/chapter7/binaryprotection/ [2]: http://osxbook.com/book/bonus/chapter7/tpmdrmmyth/

Re: How Apple hides new functionality in iOS: isYoMamaWearsCombatBootsActive

#100

Post by spartango »

0x0 wrote: post #97
spartango wrote: post #93

Earlier quoted context omitted.

This used to be the case, but no longer is; Apple stopped using the TPM in Intel macs shortly after they launched[1] and have not brought it back since. DSMOS.kext has another function, however; it is involved in Apple's binary protection scheme[2] for certain OSX binaries. Essentially, OSX ships with certain important binaries (such as loginwindow, SystemUIServer, Finder, and Dock) that have certain vm pages encrypt…

Yes, and before it will perform the decryption, it needs the correct "SmcDeviceKey", so I think my point still stands :)

Yea, they eschew the DRM-only TPM part to store the keys in the SMC, which does a whole host of things and doesn't protect the keys. I suppose you were sufficiently vague ;)

There's just an outstanding myth that Macs still use TPM...

Post reply on HN