Non-standard 20-round unbalanced Feistel cipher from the DarkCrypt Total Commander plugin. 64-bit block, 256-bit key. F applies a nested 256-entry byte S-box network; the key schedule expands 8 key words to 24 round-key words via an XOR recurrence followed by a multiplier-driven mixing pass. No public specification exists.
| Property | Value |
|---|---|
| Category | Block Ciphers |
| Sub-category | Block Cipher |
| Security status | 🎓 Educational Only |
| Complexity | Advanced |
| Inventor | Alexander Myasnikov (DarkCrypt “Zarya” project) |
| Year | 2009 |
| Origin | 🇷🇺 Russia |
| Source | algorithms/block/darkcrypt-breakme.js |
| Parameter | Supported values |
|---|---|
| Key sizes | 32 bytes (256 bits) |
| Block sizes | 8 bytes (64 bits) |
Status: 🎓 Educational Only
| Issue | Description | Mitigation |
|---|---|---|
| Undocumented non-standard design | No public specification or cryptanalysis exists for this cipher. Not recommended for real use. | Use AES or another vetted cipher. |
3 vectors ship with this algorithm and run in the test suite. Byte values are hexadecimal.
Vector 1 — DarkCrypt Breakme — zero key/plaintext
| Field | Value |
|---|---|
key |
0000000000000000000000000000000000000000000000000000000000000000 |
input |
0000000000000000 |
expected |
7feb8e2d688d5db8 |
Vector 2 — DarkCrypt Breakme — incrementing key/plaintext
| Field | Value |
|---|---|
key |
000102030405060708090a0b0c0d0e0f101112131415161718191a1b1c1d1e1f |
input |
0001020304050607 |
expected |
9a6f6f72a77702ac |
Vector 3 — DarkCrypt Breakme — shifted incrementing key/plaintext
| Field | Value |
|---|---|
key |
0102030405060708090a0b0c0d0e0f101112131415161718191a1b1c1d1e1f20 |
input |
1011121314151617 |
expected |
82c42b1a61929624 |