Created
October 25, 2018 09:39
-
-
Save syst3mw0rm/9b22a1eadd6cbf38474573d54cd54f0c to your computer and use it in GitHub Desktop.
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
// helper methods starts | |
var lc = ["0", "1", "2", "3", "4", "5", "6", "7", | |
"8", "9", "a", "b", "c", "d", "e", "f"]; | |
var uc = ["0", "1", "2", "3", "4", "5", "6", "7", | |
"8", "9", "A", "B", "C", "D", "E", "F"]; | |
function toHex(val, uppercase) { | |
var set = uppercase ? uc : lc; | |
return set[Math.floor(val / 16)] + set[val % 16]; | |
} | |
function toArrayBuffer(str) { | |
str = str.toLowerCase().replace(/\s/g, ""); | |
if (str.length % 2 == 1) | |
str = "0" + str; | |
var len = Math.floor(str.length / 2); | |
var buffer = new Uint8Array(len); | |
var curr = -1; | |
for (var i = 0; i < str.length; ++i) { | |
var c = str[i]; | |
var val = lc.indexOf(c); | |
if (val == -1) | |
throw Error("unexpected character") | |
if (curr === -1) { | |
curr = 16 * val; | |
} else { | |
buffer[Math.floor(i / 2)] = curr + val; | |
curr = -1; | |
} | |
} | |
return buffer; | |
} | |
function toString(arr, opts) { | |
var defaultOpts = { | |
grouping: 0, | |
rowlength: 0, | |
uppercase: true, | |
}; | |
if (opts == undefined) | |
opts = {} | |
opts = defaultOpts; | |
var str = ""; | |
var group = 0, column = 0; | |
for (var i = 0; i < arr.length; ++i) { | |
str += toHex(arr[i], opts.uppercase); | |
if (i === arr.length - 1) | |
break; | |
if (opts.grouping > 0 && ++group === opts.grouping) { | |
group = 0; | |
if (opts.rowlength > 0 && ++column === opts.rowlength) { | |
column = 0; | |
str += "\n"; | |
} | |
else | |
str += " "; | |
} | |
} | |
return str; | |
} | |
const ab2str = buf => String.fromCharCode.apply(null, new Uint16Array(buf)); | |
const ab2hex = ab => toString(new Uint8Array(ab)); | |
// helper method ends | |
async function importCryptoKey(key){ | |
return await window.crypto.subtle.importKey( | |
"raw", // can be "jwk" or "raw" | |
toArrayBuffer(key).buffer, | |
{name: 'AES-GCM'}, | |
true, // whether the key is extractable (i.e. can be used in exportKey) | |
["encrypt", "decrypt"] // can "encrypt", "decrypt", "wrapKey", or "unwrapKey" | |
) | |
}; | |
async function decrypt_a({ text, iv, key }){ | |
const arrayBuffer = await window.crypto.subtle.decrypt({ | |
name: 'AES-GCM', | |
iv: toArrayBuffer(iv).buffer | |
}, | |
await importCryptoKey(key), | |
toArrayBuffer(text).buffer, | |
); | |
return ab2hex(arrayBuffer); | |
}; | |
key = 'E52BC6CEDC2E096584B1F57D3AE6A60724C7B301EECB975813819673E6D23126'; | |
iv = 'B5DDEDB80480A649D1763BE7'; | |
encrypted_data = '37631B44E6B7DB7C404F2947F40FC629BB537BF303B728A674280C23528C3B09815BA2CD39B3844A38C4527464353A66'; | |
res = await decrypt_a({text: encrypted_data, iv, key}); | |
console.log(res); |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
returns
EEE72939E910F74104846B5BADBDDAD007A46E3392ADE713F6EE33900299C250