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Decompressing bzip2 data in Javascript

I ultimately have to consume some data from a Javascript file that looks as follows:
Note: The base64 is illustrative only.
function GetTripsDataCompressed() { return 'QlpoOTFBWSZTWdXoWuEDCAgfgBAHf/.....=='; }
GetTripsDataCompressed() returns a base64 string that is derived as an array of objects converted to JSON using JSON.NET and the resulting string then compressed to bzip2 using SharpCompress with the resulting memory stream Base64 encoded.
This is what I have and cannot change it.
I am struggling to find a bzip2 JavaScript implementation that will take the result of:
var rawBzip2Data = atob(GetTripsDataCompressed());
and convert rawBzip2Data back into the string that is the JSON array. I cannot use something like compressjs as I need to support IE 10 and as it uses typed arrays that means IE10 support is out.
So it appears that my best option is https://github.com/antimatter15/bzip2.js however because I have not created an archive and only bzip2 a string it raises an error of Uncaught No magic number found after doing:
var c = GetTripsDataCompressed();
c = atob(c);
var arr = new Uint8Array(c);
var bitstream = bzip2.array(arr);
bzip2.simple(bitstream);
So can anyone help me here to decompress a BZip2, Base64 encoded string from JavaScript using script that is IE 10 compliant? Ultimately I don't care whether it uses https://github.com/antimatter15/bzip2.js or some other native JavaScript implementation.

It seems to me the answer is in the readme:
decompress(bitstream, size[, len]) does the main decompression of a single block. It'll return -1 if it detects that it's the final block, otherwise it returns a string with the decompressed data. If you want to cap the output to a certain number of bytes, set the len argument.
Also, keep in mind the repository doesn't have a license attached. You'll need to reach out to the author if you want to use the code. That might be tricky given that the repository is eight years old.
On the other hand, the Bzip2 algorithm itself is open-source (BSD-like license), so you can just reimplement it yourself in Javascript. It's just a few hundred lines of relatively straight-forward code.

How to make SJCL and Python hashlib generate identical pdkdf2 output

I have a JavaScript app and a Python app that communicate using a key derived from a password using pbdkf2. The problem is, the generated keys don't match. I've produced a minimal test case for each.
Python
import hashlib, binascii
bytes = hashlib.pbkdf2_hmac('sha256', "password".encode(), b'', 100000)
print(binascii.hexlify(bytes).decode())
Generates: 64a868d4b23af696d3734d0b814d04cdd1ac280128e97653a05f32b49c13a29a
JavaScript
<script src="lib/sjcl.js"></script>
<script>
var hmacSHA256 = function (key) {
var hasher = new sjcl.misc.hmac(key, sjcl.hash.sha256);
this.encrypt = function () {
return hasher.encrypt.apply(hasher, arguments);
};
};
hash = sjcl.misc.pbkdf2("password", [0], 100000, 256, hmacSHA256);
console.log(sjcl.codec.hex.fromBits(hash));
</script>
Generates: 41c04f824d843d5be0ae66b3f621d3f05db7d47e7c46ee0e9171b5cbff7f3631
I'm scratching my head a lot now. I think b'' and [0] are equivalent salts, but I'm not sure. I think they both use utf-8 to encode the password, but I'm not sure. And I'm not convinced the JavaScript hmacSHA256 function exactly matches what Python is doing. Or it could be something else still.

Off the top of my head, have you checked if
hash = sjcl.misc.pbkdf2("password", "", 100000, 256);
gives the correct result?
As far as I can tell from the docs, SJCL's PBKDF2 implementation defaults to HMAC-SHA256 if you don't explicitly give it a PRF. If making that change fixes the bug, then there's probably something wrong with your hmacSHA256 wrapper.
Also, I'm not sure if specifying an empty salt as [0] really works (or is guaranteed to work in future versions, given that the format of SJCL's bitArrays is explicitly subject to change), but "" definitely should work.

This is sharing for the rest based on my recent experience.
My objective:
To generate PBKDF2 password using Python. The client will be Android (Java), and the back end will be on Flask (Python).
Issue:
While testing, I discovered that both versions (Java vs Python) produced different hashing output (all other parameters were equal - SHA256, 1000 iterations, similar SALT)
What I have found out:
Using PBKDF2 generation tools available on the internet, the Android result was an exact match, while the Python was not. So there is a good chance the Python result was somehow skewed .....
Problem solved:
While looking for possible explanation in SO, I discovered that the way I converted String to bytes in Python was somehow not entirely correct:
Original code:
dk = hashlib.pbkdf2_hmac('sha256', b'base64_message', b'salt', 1000)
Working code:
dk = hashlib.pbkdf2_hmac('sha256', base64_message.encode(), salt.encode(), 1000)
This is probably due to my lack of experience in Python. Hope this note will be of use to others, especially those who are new to Python!

Base64 HMAC SHA1 String in VBA

I'm trying to convert an ASP/VBScript OAuth library to VBA. One of the challenges is this line of code:
Get_Signature = b64_hmac_sha1(strSecret, strBaseSignature)
This function, b64_hmac_sha1 is actually a function contained in a JavaScript library. It appears to me that calling a JavaScript function from VBA is fairly impractical.
Because I know so little about encryption, it's not even clear to me what this b64_hmac_sha1 function does. Is HMAC SHA1 different from SHA1?
I half suspect I might be able to find some VBA code online to do what I need to do if I just understood what this function is actually doing. If I do not find an existing function, I could possibly write one that would use the .NET Cryptography library (you can actually call the .NET cryptography libraries from VBA if you know how).
I'm not looking for someone to convert this JavaScript to VBA. I'm only trying to understand what it is that this b64_hmac_sha1 function is outputting so I can try to find ways to achieve the same output in VBA if possible.
A copy of this JavaScript library is visible on this website. You'll have to scroll down past the VBScript to the JavaScript section.
http://solstice.washington.edu/solstice/ASP_Signing_REST_Example
Edit1:
OK, so here's the functions I ended up writing and using:
Public Function Base64_HMACSHA1(ByVal sTextToHash As String, ByVal sSharedSecretKey As String)
Dim asc As Object, enc As Object
Dim TextToHash() As Byte
Dim SharedSecretKey() As Byte
Set asc = CreateObject("System.Text.UTF8Encoding")
Set enc = CreateObject("System.Security.Cryptography.HMACSHA1")
TextToHash = asc.Getbytes_4(sTextToHash)
SharedSecretKey = asc.Getbytes_4(sSharedSecretKey)
enc.Key = SharedSecretKey
Dim bytes() As Byte
bytes = enc.ComputeHash_2((TextToHash))
Base64_HMACSHA1 = EncodeBase64(bytes)
Set asc = Nothing
Set enc = Nothing
End Function
Private Function EncodeBase64(ByRef arrData() As Byte) As String
Dim objXML As MSXML2.DOMDocument
Dim objNode As MSXML2.IXMLDOMElement
Set objXML = New MSXML2.DOMDocument
' byte array to base64
Set objNode = objXML.createElement("b64")
objNode.DataType = "bin.base64"
objNode.nodeTypedValue = arrData
EncodeBase64 = objNode.Text
Set objNode = Nothing
Set objXML = Nothing
End Function
Using this function:
Debug.Print Base64_HMACSHA1("abc", "123")
VAsMU9SSWDe9krP3Gr56nXC2dsQ=

HMAC is a construct for turning a hash function, like SHA1, into a Message Authentication Code (MAC).
Normal hash functions don't have any secret data associated with it. This means that anyone can compute the digest, assuming they have the original input. HMAC uses a secret key, so that only those in possession of the key can compute outputs.
Suppose I have a file, file.txt. I want to send this to you, and we need to make sure nobody tampers with it. Sorry, I have no clever way to represent this with just text.
me -> file.txt -> you
me -> SHA1(file.txt) -> you
Then you verify the result by computing your own SHA1 digest, and verifying it matches what I sent you.
Now suppose an attacker was in the middle. Unfortunately, because there is no secret involved, the attacker can modify the file, and compute his own file/digest pair. When you compute your version, it'll match what he sent you, and you'll be none the wiser.
me -> file.txt -> attacker -> modified.txt -> you
me -> SHA1(file.txt) -> attacker -> SHA1(modified.txt) -> you
With HMAC, we add a secret key to the computation.
me -> file.txt -> you
me -> SHA1_HMAC(file.txt, our_secret) -> you
When you compute your version, you apply the secret key as well, and the result matches. The attacker, without knowledge of the key, can't replace the digest.
me -> file.txt -> attacker -> modified.txt -> you
me -> SHA1(file.txt) -> attacker -> SHA1_HMAC(modified.txt, // DOESN'T KNOW KEY) -> you
HMAC is a very specific way of adding the secret key. Unfortunately, simple methods of just concatenating a key to the end of the file, or pre-pending it before hashing, are vulnerable to different attacks (length extension attacks, for example).
The B64 is Base64 encoding the output, to make it pretty.
What this code is ultimately doing is taking some input, and some secret key, and computing a 160-bit digest, and base64 encoding the result.
There is an implementation of SHA1 HMAC in .NET
This looks like an implementation of Base64 for VBA
I hope this answers it well enough, or clear enough. If the text is confusing, please let me know. I tried a couple routes of how to express it, and none of them seemed that clear.

You have written:
It appears to me that calling a JavaScript function from VBA is fairly impractical.
That is a misjudgment.
Javascript can be easily packaged as a Windows Script Component (WSC) and then invokved via COM, from VBA, Perl, VB6, or what-have-you.
Here's an example of packaging Javascript as a WSC and invoking it: https://stackoverflow.com/a/849970/48082
Therefore, your problem should be easily solvable.

is there any builtin javascript string hash function in newest browsers?

Everytime a new versions of browsers show up I hear about new stuff being added, like say webGL and other technologies that no one really knows if they catch up.
But I wonder if someone ever thought about such basic stuff in JS like hashing functions (MD5,SHA1 and the like).
By newest browsers I mean today's development versions too like Opera 12, Chrome 17 or Firefox 10.
Looking now for solution I found this comment on another thread here: https://stackoverflow.com/questions/7204097/short-hashing-function-for-javascript (Do you know that javascript objects already are hashtables ?). So what are these 'hashtables' ? Does it mean that I can make any string into a hash, but not an established one like md5 or sha1 but some JS build in specific ?
basically what I need to do is:
var txt="Hello world!";
var hash = txt.toSha1();

For anybody still looking for this information. There is a WebCrypto API which appears to have been finalised at the beginning of 2017.
To use it in a browser, you can find it at window.crypto.subtle which contains methods for encryption, digests etc. Documentation on the available functions here.

Paul Johnston has implemented the following algorithms in javascript
MD5, RIPEMD-160, SHA-1, SHA-256 and sha-512
You can find the source code and some examples here:
http://pajhome.org.uk/crypt/md5/
I hope this is what you were looking for.

async function sha256(source) {
const sourceBytes = new TextEncoder().encode(source);
const digest = await crypto.subtle.digest("SHA-256", sourceBytes);
const resultBytes = [...new Uint8Array(digest)];
return resultBytes.map(x => x.toString(16).padStart(2, '0')).join("");
}

Note: This answer was written in 2014 when the Web Cryptography API was not available. Do not use this in the context where cryptographic security is needed. This may be useful when you need a simple reversible encryption with "builtin" support.
When I need simple client side hashing without external libraries I use the browsers' built in atob() and btoa() functions.
window.btoa() creates a base-64 encoded ASCII string from a "string" of binary data.
function utf8_to_b64( str ) {
return window.btoa(encodeURIComponent( escape( str )));
}
The window.atob() function decodes a string of data which has been encoded using base-64 encoding.
function b64_to_utf8( str ) {
return unescape(decodeURIComponent(window.atob( str )));
}
http://caniuse.com/#search=btoa and http://caniuse.com/#search=atob shows it is hugely supported by the modern browsers
Example taken from https://developer.mozilla.org/en-US/docs/Web/API/window.btoa

Encrypting data with ruby decrypting with node

I want to encrypt some data in a ruby app and then decode it in a nodejs app. I have been trying to get this to work and now I am just trying to encrypt the same piece of data in both languages to get the same result but I can't seem to do it.
//js
var crypto = require('crypto');
var key = crypto.createHash('sha1').update('key').digest('hex');
console.log(key); // a62f2225bf70bfaccbc7f1ef2a397836717377de
var encrypted = "";
var cipher = crypto.createCipher('bf-cbc', key);
encrypted += cipher.update('text');
encrypted += cipher.final('hex');
console.log(encrypted); //outputs 4eafd5542875bd3c
So it looks like I get a hexadecimal string from the encoding.
#ruby
require 'openssl'
require 'digest/sha1'
c = OpenSSL::Cipher::Cipher.new("bf-cbc")
c.encrypt
# your pass is what is used to encrypt/decrypt
c.key = key = Digest::SHA1.hexdigest("key")
p key # a62f2225bf70bfaccbc7f1ef2a397836717377de
e = c.update("text")
e << c.final
p e # 皋?;??
Is there some sort of encoding issue that I am missing. I tried to base64 decode e but that didn't produce the same result as the node app. Any pointers?
UPDATE: So this is as close as a friend and I can get: https://gist.github.com/a880ea13d3b65a21a99d. Sheesh, I just want to encrypt something in ruby and decrypt it in node.
UPDATE2: Alright, the code in this issue gets me a lot of the way there: https://github.com/joyent/node/issues/1395

There are several subtle things that make this fail. The most important one - you are not specifying an IV in your code, so a random value will be generated for you. You would notice that you couldn't even decrypt your ciphertext within the same programming language this way.
So you need to provide an explicit IV to both implementations. But before I show you the code, some advice:
Key generation:
Blowfish operates on 64 bit blocks, its key size varies, but OpenSSL (which currently powers both Ruby's and node.js' cipher implementation) uses 128 bit by default, that is 16 bytes.
So your key violates two principles - the first: it's simply too long. It's the hex representation of a SHA-1 hash, which is 20 bytes * 2 = 40 bytes instead of 16. Most of the time this is fine, because the implementation truncates the values appropriately, but that is something you should not depend on.
The second mistake, much more severe, is that you use the hex representation instead of the raw bytes: big security issue! Hex characters are not random at all, so in effect you reduce the entropy of your input to half the length (because the underlying bytes were random).
A secure way to generate random keys is using OpenSSL::Random
key = OpenSSL::Random.random_bytes(cipher_key_len)
A third mistake is to keep your key hard-coded in the sources. It's a bad idea. The least you should do is to store it elsewhere on the file system, where access is tightly restricted. See also my answer to another question. The key should be stored out-of-band and only loaded dynamically within the application.
Cipher:
Blowfish grows old. It's still considered unbroken in the sense that brute-forcing it is the only way to break it. But a search space of 2^64 is not out of reach for resourceful attackers. So you should indeed move on to AES.
Padding:
OpenSSL pads using PKCS5Padding (also known as PKCS7Padding) by default. Ruby profits from this and my bet is node.js utilizes this, too - so you should be safe on this.
Now to the working solution. We need to generate an IV, Blowfish requires it to be 64 bit - 8 bytes. You will need rbytes to get secure random numbers in node. The IV may be hardcoded in your sources (it's public information, no security impact) - but it must be the same on both sides. You should pregenerate a value and use it for both node.js and Ruby.
/*node.js*/
var rbytes = require('rbytes');
var iv = rbytes.randomBytes(8);
/*see advice above - this should be out-of-band*/
var key = rbytes.randomBytes(16);
var encrypted = "";
var cipher = crypto.createCipheriv('bf-cbc', key, iv);
encrypted += cipher.update('text');
encrypted += cipher.final('hex');
Now the Ruby part:
require 'openssl'
c = OpenSSL::Cipher::Cipher.new("bf-cbc")
c.encrypt
# should be out-of-band again
c.key = OpenSSL::Random.random_bytes(16)
# may be public but has to be the same for Ruby and node
iv = OpenSSL::Random.random_bytes(8)
c.iv = iv
e = c.update("text")
e << c.final
puts e.unpack('H*')[0]

Your cyphertext will be some random looking bytes. Those bytes can be expressed as hex, Base64 or in other ways. It looks as if your ruby code is outputting the raw bytes. I suggest that you convert those raw bytes to hex to make your comparison.
Looking at your code, you should also change from Blowfish ("bf") to AES. Blowfish has a 64-bit block size and is now obsolete.
You would do well to explicitly specify padding, PKCS7 is common

OK. I want to thank everyone for helping me out. Basically this thread here answers my question: https://github.com/joyent/node/issues/1395. I am going to go ahead and post the two programs in case anyone else has to go through this rigamarole. Keep in mind this isn't mean to be hardcore secure, this is a stepping stone for ruby encrypting data and node decrypting it. You will have to take more steps to make sure higher security measures are taken.
The code is located at this gist: https://gist.github.com/799d6021890f34734470
These were run on ruby 1.9.2p290 and node 0.4.10