In a Rails 3.0 (Ruby 1.9.2) app I'm trying to encrypt some data using something like this:
cipher = OpenSSL::Cipher.new 'aes-256-cbc'
cipher.encrypt
cipher.key = cipher.random_key
cipher.iv = cipher.random_iv
encrypted = cipher.update 'most secret data in the world'
encrypted << cipher.final
That will go into a UTF-8 database. My problem is that
> encrypted.encoding
=> #<Encoding:ASCII-8BIT>
> encrypted.encode 'utf-8'
Encoding::UndefinedConversionError: "\xF7" from ASCII-8BIT to UTF-8
How can I get an UTF-8 encrypted string?
The solution is to convert the ASCII-8BIT string to Base64 and then encode to UTF-8.
cipher = OpenSSL::Cipher.new 'aes-256-cbc'
cipher.encrypt
cipher.key = cipher.random_key
cipher.iv = cipher.random_iv
encrypted = cipher.update 'most secret data in the world'
encrypted << cipher.final
encoded = Base64.encode64(encrypted).encode('utf-8')
Once persisted and retrieved from the database,
decoded = Base64.decode64 encoded.encode('ascii-8bit')
and finally decrypt it.
PS: If you're curious:
cipher = OpenSSL::Cipher.new 'aes-256-cbc'
cipher.decrypt
cipher.key = random_key
cipher.iv = random_iv
decrypted = cipher.update encoded
decrypted << cipher.final
> decrypted
=> 'most secret data in the world'