cryptography - How does 7-zip check if the password you have provided is right? -


i'm trying understand how 7-zip recognizes if password have provided correct.

for example have file x.7z have password protected "password". before attempt opening it, interface asks me password. how 7zip check if password right before attempts unzip file , fail?

it's encrypting file using aes password key. these things try decrypt block knows value of (like header that's same every 7z file), , comparing decrypted value expects. if don't match, knows password incorrect.


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