node-rsa errors when trying to decrypt message with private key

Question

So I\'ve been trying to use node with node-rsa and javascript with jsencrypt to create a website (for an assignment) where the javascript client gets the public key generate

Answer 1

I had the same issue.

encrypt.setOptions({encryptingScheme:'pkcs1'});  //Can be 'pkcs1_oaep' or 'pkcs1'. Default 'pkcs1_oaep'.

But, it still failed.

I have changed the lib from node-rsa to ursa, like this:

privateKey.decrypt(thirdEncrypted, 'base64', 'utf8',ursa.RSA_PKCS1_PADDING);

The problem has been resolved in ursa.

Answer 2

To answer your question @Curious_Programmer be default node-rsa uses pkcs1_oaep for encryption and decryption while jsencrypt uses pkcs1. Thankfully node lets you change the encryptionScheme, what you need to do is add ...

myDecrypter.setOptions({encryptionScheme: 'pkcs1'});

under

var myDecrypter = new NodeRSA({b: 512});

and all will work like a charm, I hoped I helped you ;)

Answer 3

It seems that the ciphertext is a buffer, i.e. binary data. Then it is transported using JSON, which consists of text. You need to use a text encoding over the binary data to transport it over a text based interface.

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Check the following definition of the encrypt method:

key.encrypt(buffer, [encoding], [source_encoding]);

with the reminder that the default is 'buffer' for [encoding].

So you should be using:

var encrypted = myEncrypter.encrypt(message, 'base64', 'utf-8');

where 'base64' is for the ciphertext encoding and 'utf-8' is for the plaintext encoding.

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The decryption routine should automatically use base64 decoding of the ciphertext:

var clearMessage = myDecrypter.decrypt(message.message, 'utf8');

should be just fine.