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La guerra alla crittografia - alcune questioni tecniche

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EEF ha scritto su questo. Tra parentesi, fa una certa impressione vedere EFF supportare Apple.

Would it be easy for Apple to sign the requested cracking software?

The answer any trained security engineer will give you is "it shouldn't be." It's important to realize that if Apple's iOS signing key were ever leaked, or used to sign a malicious piece of code, it would undermine the secure boot loading sequence of the entire iOS platform. Apple has worked very hard to try to limit its devices to run only Apple-signed firmware and OS code. There are pros and cons to this approach, but Apple considers this signing key among the crown jewels of the entire company. There is no good revocation strategy if this key is leaked, since its corresponding verification key is hard-coded into hundreds of millions of devices around the world. While we don't know what internal security measures Apple takes with its signing key, we should hope they are very strict. Apple would not want to store it on Internet-connected computers, nor allow a small group of employees to abscond with it or to secretly use the key on their own. It is most likely stored in a secure hardware module in a physical vault (or possibly split across several vaults) and requires several high-level Apple personnel to unlock the key and sign a new code release. A rough comparison showing the complexity that is involved in making high-assurance digital signatures is the DNSSEC Root KSK signing ceremony process (for which video is available online). This is a complicated procedure involving dozens of people. Whatever Apple's process is, it's not something they want to undertake frequently. This enables a deliberately slow and costly security process. If the government begins routinely demanding new phone-specific cracking software, this could overwhelm the security of this process by requiring many more signatures. This is another valid reason why Apple is right to fight this order.