crypto in Rails 2.x?

rubyonrails-talk
1

depends on what you are looking for. if want to have a one-way function (for passwords and such) just try it like this:

  encrypted_item = Digest::SHA256.hexdigest(“string_to_encrypt”)

you could also use SHA1, SHA384, SHA512 depending on your need of security.

2

MaD wrote:

depends on what you are looking for. if want to have a one-way function (for passwords and such) just try it like this:

  encrypted_item = Digest::SHA256.hexdigest(�string_to_encrypt�)

you could also use SHA1, SHA384, SHA512 depending on your need of security.

Thanks, but I need to decrypt it also. It is "for your eyes only" user data.

thanks, jp

3

There is a ruby-aes-normal gem. I have never used it. Have you looked at?

Cheers–

Charles

4

I'm not a cryptographer, but .... One way you could do this, depending on your app requirements, is to follow an asymmetric encryption strategy using pub/priv keys, something like:

### gen pub/priv keys to use:

$ cd ./private $ openssl genrsa -out asym_priv.key 2048 ... $ openssl rsa -in asym_priv.key -out asym_pub.key -pubout ... $ chmod 400 asym_priv.key $ chmod 444 asym_pub.key $ cd ..

### cat ./app/model/cryptor.rb

require 'digest/sha2' require 'openssl'

class Cryptor

  include Singleton

  ASYM_PUB_KEY = OpenSSL::PKey::RSA.new(IO.read("#{RAILS_ROOT}/private/ asym_pub.key"))   ASYM_PRIV_KEY = OpenSSL::PKey::RSA.new(IO.read("#{RAILS_ROOT}/ private/asym_priv.key"))   ...

  def Cryptor.asym_encrypt(str)     return Base64.encode64(ASYM_PUB_KEY.public_encrypt(str))   end

  def Cryptor.asym_decrypt(str)     return ASYM_PRIV_KEY.private_decrypt(Base64.decode64(str))   end   ... end

### and then test it out:

$ ./script/console ...

enc_str = Cryptor.asym_encrypt('testing 1 2 3')

=> "i4d/uc6w1NGCUQLspM7CMsvNMd +4dFrx3yb0QhM4N3di6Yha8jeW5Ftx4ZA2\nnPn4AzhZPzCrQdds/ERP0Lb9X/ dzJaJt5Tyig12hl4EqlILTnSj9SlPatIr9\n2m9D0K416BRuCJaWOp0lhXIe1XCZisjKKhLhR1T3nH +NjQnNx4HBFhrFOnSz \nuWpNfQf8sYxhLiSiKwTy3WUPmSRHPgu8h5mIgtxjU12spf0NvbZEDzwP+/br \nWMJNQ6rGSNP6smd3YahoQzYjNFn3v+YCjG497eIdHNOBN6LAnW+HoB1TD5qm \ngJzuOIk1eownT9kfjiykR+lNmw1kNX3bzDqdBvsB8g==\n"

dec_str = Cryptor.asym_decrypt(enc_str)

=> "testing 1 2 3"

Using Base64 isn't necessary if your db tbls can handle binary, but it can be a help when you're testing/debugging. Also, the size of your priv key in bits will definitely effect performance of encrypt/decrypt process, so you'll want to choose according to needs, balancing performance vs encrypt-strength.

And if such an asym strategy is just too slow for your needs, then you could pursue a symmetric strategy instead, which would be much faster in terms of performance, but more complex to implement (likely having to persist the initialization vector -- iv -- val used when sym encrypting some val for later use when sym decrypting that val again).

Jeff