Merge pull request #7 from Besermenji/vb/sign-pdf

Pdf files are now signed

Gemfile

@@ -6,6 +6,7 @@ gem 'sinatra'
 # Gems for pdf generation
 gem 'pdfkit'
 gem 'wkhtmltopdf-binary'
+gem 'origami'
 
 group :development, :test do
   gem 'awesome_print'

Gemfile.lock

@@ -15,6 +15,7 @@ GEM
     mime-types (3.1)
       mime-types-data (~> 3.2015)
     mime-types-data (3.2016.0521)
+    origami (1.2.7)
     pdfkit (0.8.2)
     pony (1.11)
       mail (>= 2.0)
@@ -47,6 +48,7 @@ PLATFORMS
 DEPENDENCIES
   awesome_print
   letter_opener
+  origami
   pdfkit
   pony
   pry

report_generator.rb

@@ -3,10 +3,13 @@
 require 'pry' unless ENV['RACK_ENV'] == 'production'
 require 'pony'
 require 'json'
-
+require 'openssl'
+require 'origami'
 
 class ReportGenerator < Sinatra::Base
 
+  include Origami
+
   use Rack::Auth::Basic, "Restricted Area" do |username, password|
 
     if ENV['RACK_ENV'] == 'production'
@@ -27,8 +30,7 @@ class ReportGenerator < Sinatra::Base
                 :from => '[email protected]',
                 :subject => 'hi',
                 :body => "Hello there. It is #{DateTime.now}. Enjoy your KIF report.",
-                :attachments => {"KIF_report_#{DateTime.now}.pdf" => File.read(@file)})
-
+                :attachments => {"KIF_report_#{DateTime.now}.pdf" => File.read(@output_file)})
     status 200
   end
 
@@ -39,7 +41,7 @@ class ReportGenerator < Sinatra::Base
                 :from => '[email protected]',
                 :subject => 'hi',
                 :body => "Hello there. It is #{DateTime.now}. Enjoy your KUF report.",
-                :attachments => {"KUF_report_#{DateTime.now}.pdf" => File.read(@file)})
+                :attachments => {"KUF_report_#{DateTime.now}.pdf" => File.read(@output_file)})
 
     status 200
   end
@@ -74,6 +76,71 @@ def generate_pdf(pdf_path)
     headers['Content-Type'] = 'application/pdf'
     @file_name = "pdf_test#{Time.now.getutc}"
     @file = kit.to_file(@file_name)
+    sign_pdf
+  end
+
+  def sign_pdf
+    # Code below is based on documentation available on
+    # http://www.ruby-doc.org/stdlib-1.9.3/libdoc/openssl/rdoc/OpenSSL.html
+    key = OpenSSL::PKey::RSA.new 2048
+
+    open 'private_key.pem', 'w' do |io| io.write key.to_pem end
+    open 'public_key.pem', 'w' do |io| io.write key.public_key.to_pem end
+
+    cipher = OpenSSL::Cipher::Cipher.new 'AES-128-CBC'
+    pass_phrase = if ENV['RACK_ENV'] == 'production'
+                    ENV['PDF_PASSWORD']
+                  else
+                    "admin"
+                  end
+
+    key_secure = key.export cipher, pass_phrase
+
+    open 'private_key.pem', 'w' do |io|
+      io.write key_secure
+    end
+
+    #Create the certificate
+
+    name = OpenSSL::X509::Name.parse 'CN=PDF_signature'
+
+    cert = OpenSSL::X509::Certificate.new
+    cert.version = 2
+    cert.serial = 0
+    cert.not_before = Time.now
+    cert.not_after = Time.now + 3600
+
+    cert.public_key = key.public_key
+    cert.subject = name
+
+
+    @output_file = "pdf_signed_test#{Time.now.getutc}"
+
+    contents = ContentStream.new.setFilter(:FlateDecode)
+    contents.write @output_file,
+                   :x => 350, 
+                   :y => 750, 
+                   :rendering => Text::Rendering::STROKE, 
+                   :size => 30
+
+    @pdf = PDF.read(@file)
+
+    sigannot = Annotation::Widget::Signature.new
+    sigannot.Rect = Rectangle[:llx => 89.0, :lly => 386.0, :urx => 190.0, :ury => 353.0]
+    page = @pdf.get_page(1)
+    page.add_annot(sigannot)
+
+    # Sign the PDF with the specified keys
+    @pdf.sign(cert, key, 
+      :method => 'adbe.pkcs7.sha1',
+      :annotation => sigannot,
+      :location => "Serbia", 
+      :contact => "[email protected]", 
+      :reason => "Proof of Concept"
+    )
+
+    # Save the resulting file
+    @pdf.save(@output_file)
   end
 
 end