Project Juno: Draw passwords!
Upcoming SlideShare
Loading in...5
×

Like this? Share it with your network

Share

Project Juno: Draw passwords!

  • 607 views
Uploaded on

Simple project for "draw passwords, rather than typing a string". Used Life-Like Cellular Automata for hashing images.

Simple project for "draw passwords, rather than typing a string". Used Life-Like Cellular Automata for hashing images.

More in: Technology
  • Full Name Full Name Comment goes here.
    Are you sure you want to
    Your message goes here
    Be the first to comment
    Be the first to like this
No Downloads

Views

Total Views
607
On Slideshare
605
From Embeds
2
Number of Embeds
2

Actions

Shares
Downloads
1
Comments
0
Likes
0

Embeds 2

https://twitter.com 1
http://www.slideee.com 1

Report content

Flagged as inappropriate Flag as inappropriate
Flag as inappropriate

Select your reason for flagging this presentation as inappropriate.

Cancel
    No notes for slide

Transcript

  • 1. Juno [u∶no∶] draw passwords 연세대학교 수학과 설진석
  • 2. Abstract • alternative cryptographic hash function • image based • using Life-Like Cellular Automata • algorithm development
  • 3. Preliminaries • Classical Mathematics • Automata Theory
  • 4. Cryptographic Hash Function • given a function f: X → H, H = L(w{n}) • f is called cryptographic hash function if • • • Pa, b ∈ X (f(a)=f(b)) ≦ p -1 for ∀h ∈ H, “answering f (h)” is a NP-problem where • X : given set • p : desired probability • n : natural number
  • 5. Cellular Automata • In n dimensional grid, given a • • T : transition rule • • S : set of states B : neighbor Each cell’s next state is determined by current state of the cell and neighbor applied by transition rule.
  • 6. one-dimensional CA example • each row denotes step • each column denotes cell’s state history
  • 7. Life-Like Cellular Automata • In two-dimensional grid • S : “alive” or “dead” • T : “survive”, “birth”, or “death” determined by number of “alive” cells in neighbor • B : Moore neighborhood (adjacent 8 cells)
  • 8. LLCA example: Conway’s Game of Life • rule string B3/S23 • A cell survives if 2 or 3 neighbor is alive, and births if 2 neighbor is alive. Otherwise, it dies.
  • 9. Object • drawing password, rather than inserting string • using LLCA as cryptographic hash function
  • 10. Algorithm Raw Drawing Simplify Encode Hash via LLCA
  • 11. Encoding 1 0 0 0 1 Original 0 1 0 0 1 0 1 0 0 0 0 0 1 1 1 Binary 8611d Result fixed sized image = fixed sized string 8 6 1 1 d Hex
  • 12. LLCA as Hash? • LLCA is a function • • CA itself is a deterministic inverse LLCA is NP • checking answer is P • using “number of live neighbors”, so inverse can be calculated with non-deterministic turing machine
  • 13. Limitations • sparse initial state generates sparse output • • requires minimum alive cells to be meaningful value infeasible to control or calculate collision probability p
  • 14. Benefits and Applications • At least, it is valid cryptographic hash function • Calculation can be parallelized • Easy to control complexity • • • changing rule string terminating condition Can be used for signature authentication, or fingerprints
  • 15. Implementation • Using coffee-script based LLCA library “Plasmid” • • http://nyamukoong.github.io/plasmid/ Result: https://theeluwin.kr/juno/