byte-array-util

Encapsulate the handling between Buffer(Binary) and Hex data(String), very useful for situation that processing TCP/UDP data stream, e.g. handling the binary hardware protocol data, support AES 256 algorithm encrypt and decrypt.

Installation

$ npm install byte-array-util

Usage

Usage:

var baUtil = require( 'byte-array-util' );

Data converting

/**
 * 'parseFromHexString' can get a Buffer instance from some HEX format string, it
 * will ignore all the space inside the HEX string which actually HEX string not
 * need that. For example we re-create a binary buffer from log file which has
 * the HEX data string below:
 *
 * 0x5B 0x31 0x32 0x33 0x34 0x35 0x5D <-- Equal to Ascii/UTF-8 String --> [12345]
 *
 *
 * 'toHexString' can convert a Buffer instance( Binary ) into HEX format string,
 * if you want to add some separate string between each HEX string( 2 bytes ), you
 * can set 'needSeparator' to true and provide the 'separator' param to what you
 * want.
 */
var networkDataBuffer = baUtil.parseFromHexString( '5B31323334355D' );
//var networkDataBuffer = baUtil.parseHexStringToByteArr( '5B 31 32 33 34 35 5D ' ); // same with above, space will ignore
if ( networkDataBuffer ){

    // Print the binary data
    console.log( 'networkDataBuffer( HEX ): ' + baUtil.toHexString( networkDataBuffer ) );
    console.log( 'networkDataBuffer( HEX with space separate ): ' + baUtil.toHexString( networkDataBuffer, true, ' ' ) );
    console.log( 'networkDataBuffer( UTF-8 String ): ' + networkDataBuffer.toString( 'utf-8' ) );
}
else{
    console.log( 'networkDataBuffer: null' );
}

Binary data encrypt and decrypt

/**
 * Binary buffer also can be encrypted( before you send over network ) and be
 * decrypted( after you got encrypted data from network ):
 *
 * 'encryptByAES256'
 * 'decryptByAES256'
 */
var keyString               = '#%@_My Secret Key!()*',
    keyStringBuffer         = new Buffer( keyString, 'utf-8' ),
    beforeEncryptBuffer     = new Buffer( '<Here is my scret text, please DO NOT tell anybody about this!!!>', 'utf-8' ),
    encryptedBuffer,
    decryptedBuffer;


console.log( 'keyStringBuffer(Hex): \t\t'      + baUtil.toHexString( keyStringBuffer, false, null ) );
console.log( 'keyStringBuffer(String):\t'      + keyStringBuffer.toString( 'utf-8' ) );
console.log( 'beforeEncryptBuffer(Hex):\t'     + baUtil.toHexString( beforeEncryptBuffer, false, null ) );
console.log( 'beforeEncryptBuffer(String):\t'  + beforeEncryptBuffer.toString( 'utf-8' ) );


encryptedBuffer = baUtil.encryptByAES256( beforeEncryptBuffer, keyStringBuffer );
//encryptedBuffer = baUtil.encryptByAES256( beforeEncryptBuffer, keyString );

if ( encryptedBuffer ) {
    console.log( '\nafterEncryptedBuffer(Hex):\t'  + baUtil.toHexString( encryptedBuffer, false, null ) );
    console.log( 'afterEncryptedBuffer(String):\t' + encryptedBuffer.toString( 'utf-8' ) );
}
else {
    logger.logSetting( '\nafterEncryptedBuffer', 'null' );
}


decryptedBuffer = baUtil.decryptByAES256( encryptedBuffer, keyStringBuffer );
//decryptedBuffer = baUtil.decryptByAES256( encryptedBuffer, keyString );

if ( decryptedBuffer ){
    console.log( '\nafterDecryptedBuffer(Hex):\t'  + baUtil.toHexString( decryptedBuffer, false, null ) );
    console.log( 'afterDecryptedBuffer(String):\t' + decryptedBuffer.toString( 'utf-8' ) );
}
else{
    console.log( '\nafterDecryptedBuffer', 'null' );
}