Fast Data Encipherment Algorithm by NTT. Educational implementation of a cryptographically broken Feistel cipher with 8 rounds, 64-bit blocks and keys.
| Property | Value |
|---|---|
| Category | Block Ciphers |
| Sub-category | Block Cipher |
| Security status | ❌ Broken |
| Complexity | Beginner |
| Inventor | Akihiro Shimizu, Shoji Miyaguchi |
| Year | 1987 |
| Origin | 🇯🇵 Japan |
| Source | algorithms/block/feal.js |
| Parameter | Supported values |
|---|---|
| Key sizes | 8 bytes (64 bits) |
| Block sizes | 8 bytes (64 bits) |
Status: ❌ Broken
| Issue | Description | Mitigation |
|---|---|---|
| Differential Cryptanalysis | FEAL-8 can be broken with differential cryptanalysis using only a few hundred chosen plaintexts | — |
1 vector ship with this algorithm and run in the test suite. Byte values are hexadecimal.
Vector 1 — Handbook of Applied Cryptography, Example 7.99 (FEAL-8)
| Field | Value |
|---|---|
key |
0123456789abcdef |
input |
0000000000000000 |
expected |
ceef2c86f2490752 |