Password length and time of packaging

gora2
2013-04-20
2013-04-20
  • gora2
    gora2
    2013-04-20

    Used for packaging a set of small files 2KB ... 2Mb (about 100 files)
    Files of type exe, dll, ini
    Each file is packaged in a separate archive.
    The total time of packaging:
    - No password - 13 seconds
    - Password="0" - 33 seconds
    - Password="274a8d4cfcb3c81e7f0f551b4f5477cc" - 87 seconds

    The use of a password of 1 character time increased almost 3 times, a password of 32 characters while increased almost 7 times

    Is this normal?

     
    Last edit: gora2 2013-04-20
  • Igor Pavlov
    Igor Pavlov
    2013-04-20

    Yes, it's sha-256 calculation.
    Now the only way is to change the number of iterations in source code.

     
  • gora2
    gora2
    2013-04-20

    Thank you, Igor
    We'll have to endure

     
  • why pbkdf time depends on the password size?

     
    Last edit: Bulat Ziganshin 2013-04-20
  • Igor Pavlov
    Igor Pavlov
    2013-04-20

    7z uses such function:
    SHA256(passw, 0, passw, 1, passw, 2, ...)