feat: SMIME signed notification emails

- Add mail interceptor the signs outgoing email with SMIME
- Add lib and helpers to work with SMIME data
- New configuration params for setting up SMIME key and cert files

1 files changed, 56 insertions, 0 deletions

diff --git a/spec/config/smime_signature_settings_spec.rb b/spec/config/smime_signature_settings_spec.rb
new file mode 100644
index 00000000000..4f0c227d866
--- /dev/null
+++ b/spec/config/smime_signature_settings_spec.rb
@@ -0,0 +1,56 @@
+require 'fast_spec_helper'
+
+describe SmimeSignatureSettings do
+  describe '.parse' do
+    let(:default_smime_key) { Rails.root.join('.gitlab_smime_key') }
+    let(:default_smime_cert) { Rails.root.join('.gitlab_smime_cert') }
+
+    it 'sets correct default values to disabled' do
+      parsed_settings = described_class.parse(nil)
+
+      expect(parsed_settings['enabled']).to be(false)
+      expect(parsed_settings['key_file']).to eq(default_smime_key)
+      expect(parsed_settings['cert_file']).to eq(default_smime_cert)
+    end
+
+    context 'when providing custom values' do
+      it 'sets correct default values to disabled' do
+        custom_settings = Settingslogic.new({})
+
+        parsed_settings = described_class.parse(custom_settings)
+
+        expect(parsed_settings['enabled']).to be(false)
+        expect(parsed_settings['key_file']).to eq(default_smime_key)
+        expect(parsed_settings['cert_file']).to eq(default_smime_cert)
+      end
+
+      it 'enables smime with default key and cert' do
+        custom_settings = Settingslogic.new({
+          'enabled' => true
+        })
+
+        parsed_settings = described_class.parse(custom_settings)
+
+        expect(parsed_settings['enabled']).to be(true)
+        expect(parsed_settings['key_file']).to eq(default_smime_key)
+        expect(parsed_settings['cert_file']).to eq(default_smime_cert)
+      end
+
+      it 'enables smime with custom key and cert' do
+        custom_key = '/custom/key'
+        custom_cert = '/custom/cert'
+        custom_settings = Settingslogic.new({
+          'enabled' => true,
+          'key_file' => custom_key,
+          'cert_file' => custom_cert
+        })
+
+        parsed_settings = described_class.parse(custom_settings)
+
+        expect(parsed_settings['enabled']).to be(true)
+        expect(parsed_settings['key_file']).to eq(custom_key)
+        expect(parsed_settings['cert_file']).to eq(custom_cert)
+      end
+    end
+  end
+end