NEC’s CIPHERUNICORN-E block cipher as implemented in the DarkCrypt Total Commander plugin: 16-round modified Feistel network, 64-bit block, 128-bit key, with a key-dependent linear mixing step between rounds. Matches the ISO/IEC9979-0019 reference structure except for the byte-combination step in the S-box mixing primitive, which the DarkCrypt implementation performs with subtraction instead of the reference’s plain XOR.
| Property | Value |
|---|---|
| Category | Block Ciphers |
| Sub-category | Block Cipher |
| Security status | 🎓 Educational Only |
| Complexity | Advanced |
| Inventor | NEC Corporation; DarkCrypt implementation by Alexander Myasnikov |
| Year | 1998 |
| Origin | 🇷🇺 Russia |
| Source | algorithms/block/darkcrypt-unicorn-e.js |
| Parameter | Supported values |
|---|---|
| Key sizes | 16 bytes (128 bits) |
| Block sizes | 8 bytes (64 bits) |
Status: 🎓 Educational Only
| Issue | Description | Mitigation |
|---|---|---|
| Non-standard variant | The DarkCrypt implementation deviates from the published ISO/IEC9979-0019 reference in the S-box mixing primitive’s combination step; unanalyzed as a distinct construction and 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 Unicorn — zero key/plaintext
| Field | Value |
|---|---|
key |
00000000000000000000000000000000 |
input |
0000000000000000 |
expected |
3eaeb1f9f6963069 |
Vector 2 — DarkCrypt Unicorn — incrementing key/plaintext
| Field | Value |
|---|---|
key |
000102030405060708090a0b0c0d0e0f |
input |
0001020304050607 |
expected |
13d188da49e897f6 |
Vector 3 — DarkCrypt Unicorn — shifted incrementing key/plaintext
| Field | Value |
|---|---|
key |
0102030405060708090a0b0c0d0e0f10 |
input |
1011121314151617 |
expected |
97a13f60a1481219 |