SPEED cipher as implemented by the DarkCrypt Total Commander plugin: an 8x16-bit-word unbalanced shift-register cipher with 64 rounds split into four 16-round groups, each using its own nonlinear Boolean combining function, plus a 64-word expanded key schedule. 128-bit block, fixed 256-bit key.
| Property | Value |
|---|---|
| Category | Block Ciphers |
| Sub-category | Block Cipher |
| Security status | 🎓 Educational Only |
| Complexity | Advanced |
| Inventor | Yuliang Zheng; DarkCrypt variant |
| Year | 1997 |
| Origin | 🇷🇺 Russia |
| Source | algorithms/block/darkcrypt-speed.js |
| Parameter | Supported values |
|---|---|
| Key sizes | 32 bytes (256 bits) |
| Block sizes | 16 bytes (128 bits) |
Status: 🎓 Educational Only
| Issue | Description | Mitigation |
|---|---|---|
| Non-standard variant | DarkCrypt-specific SPEED parameterization (round-group Boolean functions, key schedule) not matched to any published SPEED reference vectors; unanalyzed 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 Speed — zero key/plaintext
| Field | Value |
|---|---|
key |
0000000000000000000000000000000000000000000000000000000000000000 |
input |
00000000000000000000000000000000 |
expected |
399531b3ea9d535c2b472ba48adfefd3 |
Vector 2 — DarkCrypt Speed — incrementing key/plaintext
| Field | Value |
|---|---|
key |
000102030405060708090a0b0c0d0e0f101112131415161718191a1b1c1d1e1f |
input |
000102030405060708090a0b0c0d0e0f |
expected |
ef7717912202cea01703af3a74323942 |
Vector 3 — DarkCrypt Speed — shifted incrementing key/plaintext
| Field | Value |
|---|---|
key |
0102030405060708090a0b0c0d0e0f101112131415161718191a1b1c1d1e1f20 |
input |
101112131415161718191a1b1c1d1e1f |
expected |
638b7085b28fd4f6cdeab2f5f10a753f |