node.js and ruby 1.8 different hmac sha1 result - ruby

Question

I have ruby 1.8.7 code that create hmac with sha1
key= '123'
digest = Digest::SHA1.new
digest << 'test string'
digest << key
result = digest.hexdigest
# "c1bdfd602e1581f1ab91928e2c3fd371a1e63a5c"
I want to replicate this with node.js:
key= '123';
myhmac = crypto.createHmac('sha1', key);
result = myhmac.update('test string').digest('hex');
// 'a145f4d366e9e4e96b80bc427144ba77b3c7151a'
But the result is different.
What should I do in nodejs to have the same result as from ruby?

Answer 1

You are comparing a plain SHA1 digest in your Ruby code with a HMAC (using SHA1 as its hash function) in your Node code. These are different things, although the HMAC makes use of SHA1.
Usually you would want to use the HMAC over the plain SHA1. To do that in Ruby you could do something like:
require 'openssl'
key = '123'
data = 'test string'
digest = OpenSSL::Digest::SHA1.new
# See how HMAC uses SHA1 here:
result = OpenSSL::HMAC.hexdigest(digest, key, data)
# => "a145f4d366e9e4e96b80bc427144ba77b3c7151a", same as your node result
To reproduce your Ruby results in Node (calculating the SHA1 of the message + key), you want something like this:
const crypto = require('crypto');
const hash = crypto.createHash('sha1'); // Just SHA1, no HMAC
hash.update('test string');
hash.update('123'); // The Ruby code is hashing the concatenation of
// the data and key
result = hash.digest('hex');
// => 'c1bdfd602e1581f1ab91928e2c3fd371a1e63a5c', same as Ruby code

Answer 2

To make it works for both (nodejs and ruby), please make sure :
(important) make it in the same format.
ruby:
payload = "{'name': 'james kachiro sarumaha', 'data': [], 'is_available': true}"
payload = payload.to_json
nodejs:
payload = "{'name': 'james kachiro sarumaha', 'data': [], 'is_available': true}"
payload = JSON.stringify(payload)
have a correct key. (32)
ruby:
key = "v1tg3cOvfNdxh4TXxtdVmeB106doeQFS"
nodejs:
key = "v1tg3cOvfNdxh4TXxtdVmeB106doeQFS"
conversion
ruby :
digest = OpenSSL::Digest::SHA256.new
result = OpenSSL::HMAC.hexdigest(digest, password, payload)
#bd0724a05fab03e64e0112d09ceb11b6c1cbd8f9629a1d303e8d395d36cce396
nodejs:
crypto.createHmac('sha256', key).update(payload).digest('hex')
//bd0724a05fab03e64e0112d09ceb11b6c1cbd8f9629a1d303e8d395d36cce396
crypto from crypto module (nodejs core).
in my case, I'm using SHA256 but you can change it to SHA1. it will have the same result also.
tx