Integral Cryptanalysis
Integral cryptanalysis (the Square attack) breaks ciphers using the sum (integral) property of output bytes when an input set takes all values at certain byte positions.
Purpose
It offers distinguishers more effective than differential/linear ones for well-structured SPN ciphers (e.g., the Square attack on AES).
Mechanism
A set of plaintexts is built so that one byte ranges over 0-255 (active) while the rest are fixed (constant); after several rounds, some output byte sums to 0 (balanced), and this distinguisher attacks the remaining rounds.
Use cases
- The Square attack on AES
- SPN cipher analysis
- Block-cipher security evaluation