Comment by modeless | Hacker News Reader

Comment by modeless | Hacker News Reader

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have something on the device verify the origin and integrity of iOS images before allowing them to be installed or run.

iOS already does this. The device won't accept an iOS image unless it has been signed by Apple. Not only that, but iTunes now "verifies with Apple" over the Internet that you are allowed to install the update before proceeding. Not only that, but all binaries including App Store apps and even debug builds of apps produced by the iOS SDK must be signed.

I think Apple is using all the "effective technical measures" available to them. The only way to run code not signed by Apple is to exploit a vulnerability, and e-fuses wouldn't patch the vulnerabilities that allow jailbreaking. At best e-fuses would allow Apple to brick a jailbroken device if the owner was foolish enough to attempt an OS upgrade. The only way I could see them making iOS tighter is rewriting the whole thing in a safer language than C to cut the number of vulnerabilities.

I’m not really all that informed about the details of the iOS but didn’t Apple do this since day one, long before there even was a App Store? Before the first jailbreak came out? If it has been this way forever I see no way how you could call this ‘fighting’ jailbreaking.

Before the iPhone even came out it was obvious people would try to jailbreak them, and signed firmwares are a necessary part of jailbreak defense. You're right that Apple couldn't have been defending the App Store from jailbreaks before it was invented, but back then they did care about the carriers. They had a lot to prove. Now Apple is the darling of the industry and they have no reason to kowtow to the carriers any more, but they continue to fight jailbreaks to protect the App Store.

It used to be possible to upgrade or downgrade to a forged image through iTunes, regardless of whether you bought any software that's in it. I know a few people that upgraded to 2.0 that way.

edit: my experience seems to be irrelevant - things have changed; see ben1040's post bellow. My statement that Apple haven't done all they could have done still stands though.

[strikethrough] That has not been my experience, although I admit I haven't jailbroken an iPhone in quite a while. But this used to be how PwnageTool worked - it unzips a stock iOS image, modifies it, packages it back up, and lets you install it on your phone through iTunes.

I'm absolutely certain that this is something Apple can detect and could have prevented if they wanted to. [/strikethrough]

Also, e-fuses and trusted computing thingamajigs can be used to constantly keep the integrity of the core OS components (bootloader, kernel, launchd, etc.) in check and either brick the device or, more likely, to refuse to boot or continue running the OS until it has been restored. So, no, I disagree that Apple are using all the effective technical measures available to them. Apple are using all the measures that they think is worth investing resources in, given the magnitude of the problem (which seems to be right now tiny to nonexistent).

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