How to use the Web Crypto API to decrypt a file created using OpenSSL?

Question

I am trying to decrypt a file created using the OpenSSL command line interface. This file was created with:

openssl aes-256-cbc -a -in file.txt -out file_encrypted.txt

And can be decrypted with:

openssl aes-256-cbc -d -a -in file_encrypted.txt

Using the flag -p, I can get the actual value, salt, and IV that the WebCrypto API will require:

> openssl aes-256-cbc -d -a -p -in file_encrypted.txt
salt=F57F1CC0CD384326
key=0E971326890959386F1CFB91F185CFE109203DCEBC81DCAD4EE642F34C538E5B
iv=A884549B66400EB198879F8A09148D4E
secret text

My current attempt is as follows:

function getKey (password) {
    return crypto.subtle.digest({name: "SHA-256"}, convertStringToArrayBufferView(password)).then(function(result){
        return crypto.subtle.importKey("raw", result, {name: "AES-CBC"}, false, ["encrypt", "decrypt"]);
    });
}

function decrypt(key, data, iv) {
    return crypto.subtle.decrypt({ name: "AES-CBC", iv: iv }, key, data).then(function(result){
        var decrypted_data = new Uint8Array(result);
        return convertArrayBufferViewtoString(decrypted_data);
    }, fail);
}

var encrypted = Uint8Array.from('0E971326890959386F1CFB91F185CFE109203DCEBC81DCAD4EE642F34C538E5B'.match(/\w\w/g));
var IV = Uint8Array.from('A884549B66400EB198879F8A09148D4E'.match(/\w\w/g));

getKey(prompt('Enter decryption password:')).then(function (key) {
    decrypt(key, encrypted, IV).then(result => {
        console.log(`password: ${result}`)
    });
}, fail);

(buffer array methods for brevity - taken from http://qnimate.com/passphrase-based-encryption-using-web-cryptography-api/ )

This does not work with indefinite DOMException, although I do not know what to do next.

Answer 1

OpenSSL , , .

OpenSSL . , ; , IV .

, OpenSSL, : ", OpenSSL", OpenSSL , , , OpenSSL.

, 16- , ASCII "Salted__", .

, :

• , OpenSSL ( openssl. openssl, , , webcrypto)

• HEX ArrayBuffer hex2a convertStringToArrayBufferView

  var IV = convertStringToArrayBufferView (hex2a ('A884549B66400EB198879F8A09148D4E'));

• : base64 ( -a) 16

javascript , openssl

openssl aes-256-cbc -d -a -p -in file_encrypted.txt
enter aes-256-cbc decryption password:
salt=886DBE2C626D6112
key=0DA435C43BE722BB5BF09912E11E3E25BE826C35A674EC4284CD1C49AFBCC78E
iv =7F9608BF748309A2C7DAA63600AB3825
this is the secret value of the fiile

Javascript

//The content of file_encrypted.txt. It is encoded in base64
var opensslEncryptedData = atob('U2FsdGVkX1+Ibb4sYm1hEp/MYnmmcteeebZ1jdQ8GhzaYlrgDfHFfirVmaR3Yor5C9th02S2wLptpJC6IYKiCg==');
//Encrypted data removing salt and converted to arraybuffer
var encryptedData = convertStringToArrayBufferView(opensslEncryptedData.substr(16,opensslEncryptedData.length););

//key and IV. salt would be needed to derive key from password
var IV = convertStringToArrayBufferView (hex2a ('7F9608BF748309A2C7DAA63600AB3825'));
var key = convertStringToArrayBufferView (hex2a ('0DA435C43BE722BB5BF09912E11E3E25BE826C35A674EC4284CD1C49AFBCC78E'));
//var salt = convertStringToArrayBufferView (hex2a ('886DBE2C626D6112'));

crypto.subtle.importKey("raw", key, {name: "AES-CBC"}, false, ["encrypt", "decrypt"]). then (function (cryptokey){

    return crypto.subtle.decrypt({ name: "AES-CBC", iv: IV }, cryptokey, encryptedData).then(function(result){
        var decrypted_data = new Uint8Array(result);
        var res =  convertArrayBufferViewtoString(decrypted_data);
        console.log(res);
    }).catch (function (err){
        console.log(err);
    }); 

}).catch (function (err){
    console.log(err);
});    

function hex2a(hexx) {
    var hex = hexx.toString();//force conversion
    var str = '';
    for (var i = 0; i < hex.length; i += 2)
        str += String.fromCharCode(parseInt(hex.substr(i, 2), 16));
    return str;
}

function convertStringToArrayBufferView(str){
    var bytes = new Uint8Array(str.length);
    for (var iii = 0; iii < str.length; iii++) {
        bytes[iii] = str.charCodeAt(iii);
    }

    return bytes;
}

function convertArrayBufferViewtoString(buffer){
    var str = "";
    for (var iii = 0; iii < buffer.byteLength; iii++) {
        str += String.fromCharCode(buffer[iii]);
    }

    return str;
}

Answer 2

CMS EnvelopedData ( ) . , .

lib PKIjs ( ESK PKIjs ). . :

• CMS
• CMS

, WebCrypto, :)

Answer 3

, . @pedrofb .

WebCrypto.js (Minified) .

:

// Initialize the library
initWebCrypto();

var encrypted = "wl2v/1oY7NqV58jpSGkNKmKNu6cdNDz7QCSmKk61k9gyG2Exxh3MxXf9kuSk/ESr6MGNdtQEAhSjHZ9b+Vc4Uw==";
var key = "6f0f1c6f0e56afd327ff07b7b63a2d8ae91ab0a2f0c8cd6889c0fc1d624ac1b8";
var iv = "92c9d2c07a9f2e0a0d20710270047ea2";

// Decrypt your stuff
WebCrypto.decrypt({
    data: encrypted,
    key: key,
    iv: iv,
    callback: function(response){
        if( !response.error ){
            console.log(atob(response.result));
        }else{
            console.error(response.error);
        }
    }
});

. https://github.com/etienne-martin/WebCrypto.swift/blob/master/www/index.html.

: https://github.com/etienne-martin/WebCrypto.swift/blob/master/source.js

, !