Commit 667d69a

@@ -1,6 +1,8 @@
 module Saml
   module Kit
     class Signature
+      include ActiveModel::Validations
+
       def initialize(xml_hash)
         @xml_hash = xml_hash
       end

@@ -423,11 +423,11 @@ RSpec.describe Saml::Kit::Response do
     let(:created_at) { DateTime.now }
     let(:assertion) do
       <<-XML
-<Assertion xmlns="urn:oasis:names:tc:SAML:2.0:assertion" ID="#{id}" IssueInstant="2017-11-23T04:33:58Z" Version="2.0">
+<Assertion xmlns="#{SAML::Kit::Namespaces::ASSERTION}" ID="#{id}" IssueInstant="2017-11-23T04:33:58Z" Version="2.0">
  <Issuer>#{FFaker::Internet.uri("https")}</Issuer>
  <Subject>
    <NameID Format="#{Saml::Kit::Namespaces::PERSISTENT}">#{SecureRandom.uuid}</NameID>
-   <SubjectConfirmation Method="urn:oasis:names:tc:SAML:2.0:cm:bearer">
+   <SubjectConfirmation Method="#{SAML::Kit::BEARER}">
      <SubjectConfirmationData InResponseTo="#{SecureRandom.uuid}" NotOnOrAfter="2017-11-23T07:33:58Z" Recipient="https://westyundt.ca/acs"/>
    </SubjectConfirmation>
  </Subject>

@@ -0,0 +1,22 @@
+RSpec.describe Saml::Kit::Signature do
+  describe "#valid?" do
+    let(:key_pair) { ::Xml::Kit::KeyPair.generate(use: :signing) }
+
+    it 'returns true when the signature is valid' do
+      signed_document = Saml::Kit::AuthenticationRequest.build do |x|
+        x.sign_with(key_pair)
+      end
+      subject = described_class.new(Hash.from_xml(signed_document.to_xml))
+      expect(subject).to be_valid
+    end
+
+    it 'is invalid when the xml has been tampered' do
+      signed_document = Saml::Kit::AuthenticationRequest.build do |x|
+        x.sign_with(key_pair)
+      end
+      tampered_xml = signed_document.to_xml.gsub("Issuer", "Hacked")
+      subject = described_class.new(Hash.from_xml(tampered_xml))
+      expect(subject).to_not be_valid
+    end
+  end
+end