what would be needed to decrypt a psvimg file?

[Kankertje]

Or to edit save data to cause a buffer overflow to run homebrew.

But the saves are probably encrypted twice, just like on psp + into .img file, and there is no way to analyse the crashes, no such thing as psplink for vita

[yifanlu]

If that's the case, couldn't Sony just make their own encryption algorithm, or are there ways to decrypt an unknown algorithm if you have the key?

The first rule of computer security is to not reinvent the wheel. Encryption and security can go wrong very easily and very subtly. If you choose not to use a standard algo like RSA, which has been peer reviewed, stressed tested for years with billions of dollars and supported by governments and large corporations. Those algorithms are the safest to use. You try to make your own or even implement it yourself (see: ps3 key leak), there's no doubt you'll do it wrong. Plus, security through obscurity has never worked. Ever. Look at every drm that's been cracked and every console that's been hacked.

[alnitak]

If that's the case, couldn't Sony just make their own encryption algorithm, or are there ways to decrypt an unknown algorithm if you have the key?

The first rule of computer security is to not reinvent the wheel. Encryption and security can go wrong very easily and very subtly. If you choose not to use a standard algo like RSA, which has been peer reviewed, stressed tested for years with billions of dollars and supported by governments and large corporations. Those algorithms are the safest to use. You try to make your own or even implement it yourself (see: ps3 key leak), there's no doubt you'll do it wrong. Plus, security through obscurity has never worked. Ever. Look at every drm that's been cracked and every console that's been hacked.

That makes sense. I suppose if they do create a new algorithm, it just gets reverse engineered, at which point the keys become useful. Correct me if i'm wrong, please. Computer security isn't exactly my field.

[gregdaleg]

i dont want piracy!!!! this question was purely for educational purposes. As i am not a programmer or hacker i was just wondering. As you can probably tell i dont know much about this shit so....