Skip to content

Latest commit

 

History

History
29 lines (22 loc) · 960 Bytes

base64-custom-alt.md

File metadata and controls

29 lines (22 loc) · 960 Bytes
Raw

base64-custom THCON 2024

Challenge

Challenge

Understanding the challenge

How base64 works

  1. It takes every single letter of the word.
  2. Then it converts it into decimal.
  3. Then the decimal is converted into binary having length 8 bits.
  4. Then the binary is regrouped with every binary having length of 6 bits.
  5. Then the binary is converted into decimal.
  6. Then the decimal is converted into another character according to base64 index table.

base64-index-table

What is different in this base64custom

  • It is told that sextets are changed into quintuplets which means in the 4th step instead of 6 bits the length was 5 bits.

Contents of message.txt

KREEGTaOPNRDIcbFGYaFeMLTLcaHOMbTGBWWKXbJNZXGSdDd

Solution

  • It is same as base32 but with a condition that all the alphabets will be according to base64. b321 b322