Error handling in using Crypto in Node.js

Question

I am using Crypto library of Node.js for encryption/decryption as follows :

    encrypt = function(text, passPhrase){
        var cipher = crypto.createCipher('AES-128-CBC-HMAC-SHA1', passPhrase);
        var crypted = cipher.update(text,'utf8','hex');
        crypted += cipher.final('hex');
        return crypted;
    } ,

    decrypt = function(text, passPhrase){
        var decipher = crypto.createDecipher('AES-128-CBC-HMAC-SHA1', passPhrase)
        var dec = decipher.update(text,'hex','utf8')
        dec += decipher.final('utf8');
        return dec;
    }

There is no problem with encryption part. and if I send the correct passPhrase for decryption there is also no problem. My problem is,if I send 'wrong' passPhrase for decryption, code breaks and throw an error :

TypeError: Bad input string
    at Decipher.Cipher.update (crypto.js:279:27)
    at module.exports.decrypt (/xxxx/yyyyy/jjj/ssss/encryptionService.js:19:28)
    at Object.module.exports.passwordDecryptor (/xxxx/yyyyy/jjj/ssss/encryptionService.js:59:56)
    at Object.<anonymous> (/xxxx/yyyyy/jjj/ssss/test.js:32:33)
    at Module._compile (module.js:456:26)
    at Object.Module._extensions..js (module.js:474:10)
    at Module.load (module.js:356:32)
    at Function.Module._load (module.js:312:12)
    at Function.Module.runMain (module.js:497:10)
    at startup (node.js:119:16)

I dont want it happen. I want for example decrypt function returns 'Passpharse is wrong' sentence. According to the documentation enter link description here createDecipher function doesn't accept a callback function.

I have this challenge too. The crypto library doesn't handle an error there? — Costa, Oct 21 '15 at 05:05

score 15 · Answer 1 · answered Sep 15 '14 at 15:54

15

I solved the problem with try and catch. (The callback function doesn't work.)

 decrypt = function(text, passPhrase){
        var decipher = crypto.createDecipher('AES-128-CBC-HMAC-SHA1', passPhrase);
        try {
            var dec = decipher.update(text,'hex','utf8');
            dec += decipher.final('utf8');
            return dec;
        } catch (ex) {
            console.log('failed');
            return;
        }
    }

answered Sep 15 '14 at 15:54

Danial

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instead of console.log() you can create an err,throw it and catch it somewhere else in your code. – Danial Sep 15 '14 at 15:56
Sure would be nice to know how to catch that error when using a pipe. Ah, frameworks, obfuscation abound. – David Dombrowsky May 25 '18 at 18:49

Error handling in using Crypto in Node.js

1 Answers1