steel_crypt 1.1.1

A comprehensive library of high-level, cryptographic API's. This library supports hashing, password hashing, symmetric and asymmetric two-way encryption, and key/IV generation.

Steel Crypt

A comprehensive library of high-level, cryptographic API's, either manually defined or pulled from PointyCastle. This library currently supports hashing, symmetric two-way encryption, asymmetric two-way encryption, and key/IV generation. It also has a CLI, for conducting basic cryptography operations.

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Classes

AES Encryption (class AesCrypt)

• Constructor: AesCrypt ('32 length key', 'mode here', 'padding here')

• AES is a standardized, widely used cipher

• It can be used as either a block or stream cipher, depending on mode

• Operatable in 6 different modes:

  • Stream modes:
    • CTR ('ctr')
    • SIC ('sic')
  • Block modes:
    • CBC ('cbc') (Default)
    • ECB ('ecb')
    • CFB-64 ('cfb-64')
    • OFB-64 ('ofb-64')

• 4 paddings available for block modes:

  • PKCS7 Padding ('pkcs7') (Default)
  • ISO7816-4 Padding ('iso7816-4')
  • X9.23 Padding ('x9.23')
  • TBC Padding ('tbc')

• Note: All block modes require padding, to ensure that input is the correct block size.

• Note: Paddings do not work with stream modes. You can still enter the parameter, but it won't be used.

• Note: AES requires 16 bytes of IV.

Lightweight Stream Ciphers (class LightCrypt)

• Constructor: LightCrypt('32 length key', 'algorithm here')
• ChaCha20 stream cipher ('ChaCha20/__')
  • Derivative of Salsa20 with increased security
  • Can be used in 3 variants:
    • 20 round ( __ ==> '20' ) (Default Encryption)
    • 12 round ( __ ==> '12' )
    • 8 round ( __ ==> '8' )
  • Note: Requires 12 bytes of IV
• Salsa20 stream cipher ('Salsa20/__')
  • Secure, speedy AES alternative
  • E-Crypt Stream Cipher final portfolio
  • Can be used in 3 variants:
    • 20 round ( __ ==> '20' )
    • 12 round ( __ ==> '12' )
    • 8 round ( __ ==> '8' )
  • Note: Requires 8 bytes of IV
• HC-256 stream cipher ('HC-256')
  • Secure, software-efficient cipher
  • E-Crypt Stream Cipher final portfolio
  • Note: Requires 16 bytes of IV
• Grain-128 stream cipher ('Grain-128')
  • Secure, hardware-efficient cipher
  • E-Crypt Stream Cipher final portfolio
  • Note: Requires 12 bytes of IV
• ISAAC stream cipher ('ISAAC')
  • Extremely fast stream cipher
  • Secure, but with a low margin
  • Usage not recommended unless you have very high speed needs
  • Note: Requires no IV; you can enter an IV param, but it won't affect anything

2-Way Asymmetric (class RsaCrypt)

• Constructor: RsaCrypt()
• RSA with OAEP padding
• Note: RsaCrypt auto generates secure RSA private and public keys. You can access them using .privKey and .pubKey getters, or use your own.

Password Hashing (class PassCrypt)

• Constructor: PassCrypt()
• PBKDF2 with SHA-256 and HMAC
• Compare plaintext to hashtext using .checkPassKey(salt, plain, hashed, length)

Hashing (class HashCrypt)

• Constructor: HashCrypt('algorithm here')
• SHA-3 ('SHA-3/___') :
  • /224
  • /256
  • /384
  • /512 (Default Hash)
• SHA-2 ('SHA-___'):
  • -224
  • -256
  • -384
  • -512
• SHA-1 ('SHA-1') UNSECURE
• Tiger ('Tiger')
• Blake2b ('Blake2b')
• RipeMD ('RIPEMD-___'):
  • -128
  • -160
  • -256
  • -320
• MD5 ('MD5') UNSECURE
• MD4 ('MD4') UNSECURE
• MD2 ('MD2') UNSECURE
• Note: Compare plaintext to hashtext using .checkpass(plain, hashed)

MAC's (class MacCrypt)

• Constructor: MacCrypt ('32 length key', 'CMAC or HMAC', 'algorithm here')
• HMAC and CMAC are available
  • For HMAC algorithm field, use any available hashing algorithm as in HashCrypt
  • For CMAC algorithm field, use any available AES block cipher algorithm as in AESCrypt

Key/IV Generation (class CryptKey)

• Constructor: ```CryptKey()``
• .genFortuna (int length = 32):
  • Generates cryptographic string using Fortuna algorithm
  • Slower but significantly more secure
  • Best for private keys
  • Used internally
• .genDart (int length = 16):
  • Generates cryptographic string using Dart Random.secure()
  • Faster but less secure
  • Best for IV's or salt

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Usage

A simple usage example:

//This Source Code Form is subject to the terms of the Mozilla Public
//License, v. 2.0. If a copy of the MPL was not distributed with this
//file, You can obtain one at https://mozilla.org/MPL/2.0/.

// © 2019 Aditya Kishore

import 'package:steel_crypt/steel_crypt.dart';

main() {

  var FortunaKey = CryptKey().genFortuna(); //generate 32 byte key generated with Fortuna


  var aesEncrypter = AesCrypt(FortunaKey, 'cbc', 'iso7816-4'); //generate AES CBC block encrypter with key and ISO7816-4 padding

  var aesEncrypter2 = AesCrypt(FortunaKey, 'ofb-64', 'pkcs7'); //generate AES CBC block encrypter with key and PKCS7 padding

  var streamAES = AesCrypt(FortunaKey, 'ctr'); //generate AES CTR stream encrypter with key


  var encrypter2 = RsaCrypt(); //generate RSA encrypter


  var encrypter3 = LightCrypt(FortunaKey, "ChaCha20/12"); //generate ChaCha20/12 encrypter


  var hasher = HashCrypt('SHA-3/512'); //generate SHA-3/512 hasher

  var hasher3 = MacCrypt(FortunaKey, "CMAC", 'cfb-64'); //CMAC AES CFB-64 Hasher


  var passHash = PassCrypt(); //generate PBKDF2 password hasher


  var iv = CryptKey().genDart(16); //generate iv for AES with Dart Random.secure()

  var iv2 = CryptKey().genDart(12); //generate iv for ChaCha20 with Dart Random.secure()


  var salt = CryptKey().genDart(16); //generate salt for password hashing with Dart Random.secure()


  //Print key
  print ("Key:");

  print(FortunaKey);

  print("");


  //SHA-3 512 Hash
  print("SHA-3 512 Hash:");

  print(hasher.hash('example')); //perform hash

  var hash = hasher.hash('example');

  print(hasher.checkhash('example', hash)); //perform check

  print("");

  //CMAC AES CFB-64 Hash
  print("CMAC AES CFB-64 Hash:");

  print(hasher3.process('words')); //perform hash

  var hash3 = hasher3.process('words');

  print(hasher3.check('words', hash3)); //perform check

  print("");

  //Password (SHA-256/HMAC/PBKDF2)
  print("Password hash (SHA-256/HMAC/PBKDF2):");

  print(passHash.hashPass(salt, "words")); //perform hash

  var hash4 = passHash.hashPass(salt, "words");

  print(passHash.checkPassKey(salt, "words", hash4)); //perform check

  print("");


  //12-Round ChaCha20; Symmetric stream cipher
  print("ChaCha20 Symmetric:");

  print(encrypter3.encrypt('word', iv2)); //encrypt

  String crypted3 = encrypter3.encrypt('word', iv2);

  print(encrypter3.decrypt(crypted3, iv2)); //decrypt

  print("");


  //AES CBC with ISO7816-4 padding; Symmetric block cipher
  print("AES Symmetric:");

  print(aesEncrypter.encrypt('words', iv)); //encrypt

  String crypted = aesEncrypter.encrypt('words', iv);

  print(aesEncrypter.decrypt(crypted, iv)); //decrypt

  print("");


  //AES OFB-64 with PKCS7 padding; Symmetric block cipher
  print("AES Symmetric:");

  print(aesEncrypter2.encrypt('words', iv)); //encrypt

  String crypted2 = aesEncrypter2.encrypt('words', iv);

  print(aesEncrypter2.decrypt(crypted2, iv)); //decrypt

  print("");


  //AES CTR; Symmetric stream cipher
  print("AES Symmetric:");

  print(streamAES.encrypt('words', iv)); //encrypt

  String crypted5 = streamAES.encrypt('words', iv);

  print(aesEncrypter.decrypt(crypted5, iv)); //decrypt

  print("");


  //RSA with OAEP padding; Asymmetric
  print("RSA Asymmetric:");

  var crypted4 = encrypter2.encrypt("word", encrypter2.pubKey); //encrypt

  print(crypted4);

  print(encrypter2.decrypt(crypted4, encrypter2.privKey)); //decrypt

  print("");
}

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CLI

This CLI allows you to perform basic functions from the main package on the terminal

Setup

• If you haven't already done so, add pub-cache to your PATH with $ export PATH="$PATH":"$HOME/.pub-cache/bin"
• Globally activate the steel_crypt package with $ pub global activate steel_crypt

Commands

• encrypt: $ encrypt -t (text here) -k (key here) -i (iv here)
  • Uses AES with PKCS7 padding
  • All fields required
• decrypt: $ decrypt -t (encrypted here) -k (key here) -i (iv here)
  • Uses AES with PKCS7 padding
  • All fields required
• hash: $ hashtext -p (plain here)
  • Uses SHA-3/512
  • Field required
• make keys: $ genkey -l (length here)

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Notes

• This is fairly well-tested and documented, but use in production AT YOUR OWN RISK.
• This is relatively complete, but will get new algorithms and be actively maintained for new bugs.
• I've now added almost every algorithm from PointyCastle, and some from BouncyCastle, so every algorithm requires extensive implementation work. Bear with me!
• I need your input! What algorithms and features would you like to see here? That leads me to...
• Please file feature requests, clarifications, and bugs at the issue tracker!

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TODO's

• ✅ Create Project + add "Starter Set" of algorithms
• ✅ Add more, different hashes
• ❌ Add more, different 2-way stream algorithms (In progress...) ("LightCrypt" for updates)
• ✅ Try to add more packaging options
• ✅ Tackle adding an RSA solution
• ✅ Create a more complete password solution
• ✅ Add more detailed example
• ❌ ??? (Leave feature requests in the issue tracker, and they'll end up here!)

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Reading

• Look at these links for further information on ciphers, hashes, and terminology used here:
  • https://en.wikipedia.org/wiki/Salsa20
  • https://en.wikipedia.org/wiki/Advanced_Encryption_Standard
  • https://en.wikipedia.org/wiki/RSA_(cryptosystem)
  • https://en.wikipedia.org/wiki/SHA-3
  • https://en.wikipedia.org/wiki/SHA-2
  • https://en.wikipedia.org/wiki/SHA-1
  • https://en.wikipedia.org/wiki/MD5
  • https://en.wikipedia.org/wiki/MD4
  • https://en.wikipedia.org/wiki/Tiger_(hash_function)
  • https://en.wikipedia.org/wiki/Whirlpool_(hash_function)
  • https://en.wikipedia.org/wiki/HMAC
  • https://en.wikipedia.org/wiki/OAEP
  • https://en.wikipedia.org/wiki/Padding_(cryptography)#PKCS#5_and_PKCS#7
  • https://en.wikipedia.org/wiki/Initialization_vector
  • https://en.wikipedia.org/wiki/Cryptographic_hash_function
  • https://en.wikipedia.org/wiki/Symmetric-key_algorithm
  • https://en.wikipedia.org/wiki/Public-key_cryptography

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©2019 Aditya Kishore

Licensed under the Mozilla Public License 2.0