File encryption/decryption needed

Hi Folks,

         Yesterday, in my ruby application, I was needed to

encrypt/decrypt a file. I searched for a 2-way encryption technique and
ended up with ezcrypto gem. I thought to give it a test. I was able to
encrypt the content and store it in a file but getting errors while
decrypting the file content and writing to console. I couldn’t figure
out the problem. here is my code

require ‘rubygems’
require ‘ezcrypto’

@key = EzCrypto::Key.with_password “private documents”,“salted hash”
file1 = File.new(“crypto.txt”, “w”)
@encrypted = @key.encrypt “These are private documents”
file1.puts @encrypted
file1.close
puts “Here is the content”
file2 = File.read(“crypto.txt”)
puts @key.decrypt file2

Can anyone figure out the problem? or suggest me a different crypting
technique other than ezcrypto or suggest me a ruby app implementing such
a requirement…
or a code snippet

any help appreciated

thanks&regards,
Venkat

On Sep 18, 2007, at 2:15 AM, Venkat B. wrote:

require ‘rubygems’
require ‘ezcrypto’

@key = EzCrypto::Key.with_password “private documents”,“salted hash”
file1 = File.new(“crypto.txt”, “w”)
@encrypted = @key.encrypt “These are private documents”
file1.puts @encrypted
file1.close
puts “Here is the content”
file2 = File.read(“crypto.txt”)
puts @key.decrypt file2

I think puts is adding a “\n” at the end of the file you write out as
crypto.txt. So from the point of view of @key.decrypt the file has
been corrupted. Try the following:

@key = EzCrypto::Key.with_password "private documents","salted hash" File.open("crypto.txt", "w") do |file1| @encrypted = @key.encrypt "These are private documents" file1.write @encrypted end puts "Here is the content" file2 = File.read("crypto.txt") puts @key.decrypt file2

I couldn’t test the above code because I don’t have the ezcrypt gem.

Regards, Morton

-------- Original-Nachricht --------

Datum: Tue, 18 Sep 2007 15:15:28 +0900
Von: Venkat B. [email protected]
An: [email protected]
Betreff: file encryption/decryption needed

require ‘ezcrypto’
Can anyone figure out the problem? or suggest me a different crypting
http://www.ruby-forum.com/attachment/304/test.rb


Posted via http://www.ruby-forum.com/.

Dear Venkat,

I tried your code and I got a problem about “wrong final block length
(OpenSSL::Cipher)”, which comes from the fact that you are writing
an additional newline at the end of the encrypted text when
you store it in a file.
So read in the encrypted text from that file, chop off the last newline,
and decrypt:

require ‘rubygems’
require ‘ezcrypto’
@key = EzCrypto::Key.with_password “mighty mouse”,“salted hash”
file1 = File.new(“crypto.txt”, “w”)
@encrypted = @key.encrypt “This is my super-secret message”
file1.puts @encrypted
file1.close
file2=File.read(“crypto.txt”).chop
puts @key.decrypt(file2) # => “This is my super-secret message”

Best regards,

Axel

Dear Axel,

         Thanks. It works great. I have been trying for two days but 

unable to
figure out that. I need to be little bit careful with files.

once again, thanks to you and the forum…

regards,
venkat