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So, I have the encryption and decryption methods on ruby and they work fine ruby. I followed the answer from this question (How to decrypt message with CryptoJS AES. I have a working Ruby example) but it's returning an empty string.
Ruby Code
def load_vars
@key = "2e35f242a46d67eeb74aabc37d5e5d05"
@algorithm = "aes-128-cbc"
end
def encryption(data)
begin
key = @key
aes = OpenSSL::Cipher.new(@algorithm)
aes.encrypt()
aes.key = key
iv_value = aes.random_iv
aes.iv = iv_value
crypt = aes.update(data) + aes.final()
crypt_string = (Base64.encode64(iv_value + crypt))
return crypt_string
end
end
def decryption(data)
begin
key = @key
aes = OpenSSL::Cipher.new(@algorithm)
iv_value = Base64.decode64(data)[0...16]
data_value = Base64.decode64(data)[16..-1]
aes.decrypt
aes.key = @key
aes.iv = iv_value
results = aes.update(data_value) + aes.final
return results
end
end
HTML JSFIDDLE
<script src="https://cdnjs.cloudflare.com/ajax/libs/crypto-js/3.1.2/components/core-min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/crypto-js/3.1.2/rollups/aes.js"></script>
<script>
data = "wlkAKa4ps+Xizx4VIdUSp43yfQvOmt9FNlVTQ1ANsCU=\n"; // The data received from the ruby encryption method
key = "2e35f242a46d67eeb74aabc37d5e5d05";
// Decode the base64 data so we can separate iv and crypt text.
var rawData = atob(data);
var iv = rawData.substring(0,16);
var crypttext = rawData.substring(16);
// Decrypt...
var plaintextArray = CryptoJS.AES.decrypt(
{ ciphertext: CryptoJS.enc.Latin1.parse(crypttext) },
CryptoJS.enc.Hex.parse(key),
{ iv: CryptoJS.enc.Latin1.parse(iv) }
);
console.log(CryptoJS.enc.Latin1.stringify(plaintextArray));
</script>
514
CryptoJS supports AES-128, AES-192, and AES-256. It will pick the variant by the size of the key you pass in. If you use a passphrase, then it will generate a 256-bit key. DES is a previously dominant algorithm for encryption, and was published as an official Federal Information Processing Standard (FIPS).
In case of AES-256 - block size is, obviously, 256 bits, which is 32 bytes, which is exactly what you get by CryptoJS. enc. Base64. parse() of 22 byte Base64 string. According to specification and algorithm, IV is exactly block size length, which is 32 bytes with AES-256.
It means that the key (secret passphrase) used to encrypt and decrypt is the same. So, it's security relies mostly in keeping the key secure. If someone obtains the key, they will be able to decrypt anything encrypted with that passphrase.
The problem is that Ruby expects the key to be in binary format, not hex. So you need to do this:
#!/usr/bin/env ruby
require 'openssl'
require 'base64'
data = "When in Rome do as the Romans do"
key = "2e35f242a46d67eeb74aabc37d5e5d05"
aes = OpenSSL::Cipher.new("aes-128-cbc")
aes.encrypt()
aes.key = key.scan(/../).collect{|x| x.hex}.pack("c*")
iv_value = aes.random_iv
aes.iv = iv_value
crypt = aes.update(data) + aes.final()
crypt_string = (Base64.encode64(iv_value + crypt))
puts crypt_string
For me that prints
mdnLCY6MdwEONY1AxR/vjVKMssB+yrPsz4QMjfl6fDXxv68E0EUxtAqa4VUo
fTkjq2Hqyd48UV3dyWmEbwXw5Q==
If I put that into your HTML file (without changing any code), I get back the original message:
<!DOCTYPE html>
<html>
<head>
<script src="https://cdnjs.cloudflare.com/ajax/libs/crypto-js/3.1.2/components/core-min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/crypto-js/3.1.2/rollups/aes.js"></script>
<script>
data = "mdnLCY6MdwEONY1AxR/vjVKMssB+yrPsz4QMjfl6fDXxv68E0EUxtAqa4VUo\nfTkjq2Hqyd48UV3dyWmEbwXw5Q==\n";
key = "2e35f242a46d67eeb74aabc37d5e5d05";
var rawData = atob(data);
var iv = rawData.substring(0,16);
var crypttext = rawData.substring(16);
// Decrypt...
var plaintextArray = CryptoJS.AES.decrypt(
{ ciphertext: CryptoJS.enc.Latin1.parse(crypttext) },
CryptoJS.enc.Hex.parse(key),
{ iv: CryptoJS.enc.Latin1.parse(iv) }
);
console.log(plaintextArray);
console.log(CryptoJS.enc.Latin1.stringify(plaintextArray));
</script>
</head>
<body>
</body>
</html>
So the problem is that your Ruby code produced a gibberish cyphertext. Fix the key and re-encrypt, and the JS should start working.
117
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