BBC keystream/permutation cipher from the DarkCrypt Total Commander plugin. Exposed through the block interface with a 256 KiB block, but internally three additive lagged-Fibonacci generators (seeded from 3 key bytes) build sixteen key-dependent S-boxes for two chained substitution passes plus a full-block involution shuffle.
| Property | Value |
|---|---|
| Category | Block Ciphers |
| Sub-category | Block Cipher |
| Security status | 🎓 Educational Only |
| Complexity | Intermediate |
| Inventor | Alexander Myasnikov (DarkCrypt plugin) |
| Year | 2013 |
| Origin | 🇷🇺 Russia |
| Source | algorithms/block/darkcrypt-bbc.js |
| Parameter | Supported values |
|---|---|
| Key sizes | 12 bytes (96 bits) |
| Block sizes | 262144 bytes (2097152 bits) |
Status: 🎓 Educational Only
| Issue | Description | Mitigation |
|---|---|---|
| Tiny effective key | Only the first 3 of the 12 key bytes influence the output, giving at most a 24-bit effective key space that is trivially brute-forced. | Do not use for confidentiality; use AES or another vetted cipher. |
| Non-standard construction | Ad-hoc lagged-Fibonacci keystream with key-derived S-boxes; unanalyzed and not recommended for real use. | Use a vetted cipher. |
1 vector ship with this algorithm and run in the test suite. Byte values are hexadecimal.
Vector 1 — DarkCrypt Bbc — zero key, all-zero 256 KiB plaintext
| Field | Value |
|---|---|
key |
000000000000000000000000 |
input |
00000000000000000000000000000000 00000000000000000000000000000000 00000000000000000000000000000000 00000000000000000000000000000000 … (262144 bytes; the full value is in the source) |
expected |
0dc1a6bce4a38eb7f824a3af534d5916 5fce0f92df67ac6ebfff147190ef38d1 40e9906aedc24aaa2fbdeb06dc040bf1 35d8dc38ba4772c512ed60780fddfb53 … (262144 bytes; the full value is in the source) |