gost89

Gost89
======

Gost89 cipher and hash function implementation in JS


Algos
-----

* DSTU Gost 34311-95 hash function
* DSTU Gost 28147-2009 CFB mode block cipher
* DSTU Gost 28147-2009 ECB mode block cipher
* DSTU Gost 28147 key wrapper as specified by DSTSZI [0]
* PBKDF (Gost-34311 based)
* Dumb KDF (N-iterations of hash)

[0] http://dstszi.kmu.gov.ua/dstszi/control/uk/publish/article?showHidden=1&art_id=90096&cat_id=38837

GOST-DSTU Notice
----------------

This package implements GOST functions, however S-BOX used by default comes
from Ukrainian counterpart standard DSTU as original GOST does not specify
explicitly what table to use.

Examples
--------

All function except Hash.update() accept buffer objects, string or byte arrays.

Hash messages:
``js
var gost89 = require("gost89");
var hash = gost89.gosthash("LA LA LA SHTIRLITZ KURWA VODKA MATRIOSKA");
//

var hash_ctx = gost89.Hash.init();
hash_ctx.update("ARBITARY SIZED VODKA");
hash_ctx.update("VODKA VODKA MORE VODKA");
var hash = hash_ctx.finish(Buffer.alloc(32));
//

hash_ctx.reset();
hash.update32(buffer_of_32_bytes);
var hash = hash_ctx.finish(Buffer.alloc(32));
`


Encrypt message:

`js
var gost = gost89.init();
var clear = Buffer.from('lol', 'binary');
gost.key(Buffer.alloc(32));
var out = gost.crypt(clear, out);
`

Encrypt messages in CFB mode:

`js
var gost = gost89.init();
var out = gost.crypt_cfb(iv, clear);
// out contains encrypted text
`


Properly encrypt message:

`js
var gost = gost89.init();
var key = crypto.randomBytes(32);
gost.key(key);
var enc = gost.crypt(text, enc);

var iv = crypto.randomBytes(8);
var shared_key = some_diffie_hellman_here(me, you); // see jkurwa
var wrapped_key = gost89.wrap_key(key, shared_key, iv);
// send enc and wrapped_key to other party
``