4 ms·

> We simply want the chance, with a search warrant, to try to guess the terrorist’s passcode without the phone essentially self-destructing and without it takin

> We simply want the chance, with a search warrant, to try to guess the terrorist’s passcode without the phone essentially self-destructing and without it taking a decade to guess correctly. That’s it. Bull crap. The FBI has it within their power to break the encryption in less than a decade by spinning up tens of thousands of EC2 GPU instances. Forcing Apple to develop products that don't yet exists is simply a choice of economy, with the added benefit of being able to strongarm any other business into creating new products in the future if it suits the FBI.

tzs 11y ago
> Bull crap. The FBI has it within their power to break the encryption in less than a decade by spinning up tens of thousands of EC2 GPU instances. How? They either need to break the PIN or they need to break the AES256 key that is used to encrypt file metadata. They cannot use EC2 GPU instances to attack the PIN because the function that derives the AES key from the PIN uses a key that is unique to each phone and not readable by software so they cannot get a hold of it unless they resort to opening the crypto chip and trying to read the key by examining the hardware (and if they do that, they won't need a GPU...any desktop computer would be able to brute force the PIN quickly). They can use EC2 GPU instances to go after the AES256 key for metadata encryption, but that will take a hell of a lot longer than a decade.
- deleted 11y ago
  [deleted]
  - tzs 11y ago
    AES256 has 115, 792, 089, 237, 316, 195, 423, 570, 985, 008, 687, 907, 853, 269, 984, 665, 640, 564, 039, 457, 584, 007, 913, 129, 639, 936 possible keys (I've put spaces after the commas to allow HN to wrap because HN can have trouble with long strings lacking whitespace). Suppose Amazon has some kind of super GPU that can try 1 trillion (10^12) keys per clock cycle, and rans at 1 THz (!0^12 Hz). Note that both of these far exceed any actual GPUs. Suppose Amazon has a trillion of these available and you use them all. To search that entire key space would take 3669308250866118434801967410403995 years. On average you only have to search half the key space, which cuts this 1834654125433059217400983705201998 years. Assuming that this computation can be done super efficiently...so efficiently that for each key tested only a single bit actually has to irreversibly change state, and that we are doing this in a system cooled by liquid helium, it would need a minimum amount of energy equal to the entire energy output of the Sun over 3.6x10^20 years. (I don't remember if that is worst case or average, so let's be generous and call it only 1.8x10^20 years worth of total solar energy output).
  - wolf550e 11y ago
    Do you understand what "two raised to the 256th power" means? No, you can't bruteforce AES-256 in years or decades, even if you owned Amazon and were willing to use all the servers for this.
tptacek 11y ago
No. https://www.reddit.com/r/theydidthemath/comments/1x50xl/time_and_energy_required_to_bruteforce_a_aes256/ https://www.reddit.com/r/theydidthemath/comments/1x50xl/time...

tzs 11y ago

> Bull crap. The FBI has it within their power to break the encryption in less than a decade by spinning up tens of thousands of EC2 GPU instances. How? They either need to break the PIN or they need to break the AES256 key that is used to encrypt file metadata. They cannot use EC2 GPU instances to attack the PIN because the function that derives the AES key from the PIN uses a key that is unique to each phone and not readable by software so they cannot get a hold of it unless they resort to opening the crypto chip and trying to read the key by examining the hardware (and if they do that, they won't need a GPU...any desktop computer would be able to brute force the PIN quickly). They can use EC2 GPU instances to go after the AES256 key for metadata encryption, but that will take a hell of a lot longer than a decade.

deleted 11y ago
[deleted]
- tzs 11y ago
  AES256 has 115, 792, 089, 237, 316, 195, 423, 570, 985, 008, 687, 907, 853, 269, 984, 665, 640, 564, 039, 457, 584, 007, 913, 129, 639, 936 possible keys (I've put spaces after the commas to allow HN to wrap because HN can have trouble with long strings lacking whitespace). Suppose Amazon has some kind of super GPU that can try 1 trillion (10^12) keys per clock cycle, and rans at 1 THz (!0^12 Hz). Note that both of these far exceed any actual GPUs. Suppose Amazon has a trillion of these available and you use them all. To search that entire key space would take 3669308250866118434801967410403995 years. On average you only have to search half the key space, which cuts this 1834654125433059217400983705201998 years. Assuming that this computation can be done super efficiently...so efficiently that for each key tested only a single bit actually has to irreversibly change state, and that we are doing this in a system cooled by liquid helium, it would need a minimum amount of energy equal to the entire energy output of the Sun over 3.6x10^20 years. (I don't remember if that is worst case or average, so let's be generous and call it only 1.8x10^20 years worth of total solar energy output).
- wolf550e 11y ago
  Do you understand what "two raised to the 256th power" means? No, you can't bruteforce AES-256 in years or decades, even if you owned Amazon and were willing to use all the servers for this.

tptacek 11y ago

No. https://www.reddit.com/r/theydidthemath/comments/1x50xl/time_and_energy_required_to_bruteforce_a_aes256/ https://www.reddit.com/r/theydidthemath/comments/1x50xl/time...