Initial commit

app/services/api_keys_verifier.rb

@@ -0,0 +1,17 @@
+# frozen_string_literal: true
+
+class APIKeysVerifier
+  def initialize(params = {})
+    @kid = params[:kid]
+    @signature = params[:signature]
+    @nonce = params[:nonce] || nil
+    @api_key = APIKey.find_by!(kid: @kid)
+  end
+
+  def verify_hmac_payload?
+    data = @nonce.to_s + @kid
+    algorithm = 'SHA' + @api_key.algorithm[2..4]
+    true_signature = OpenSSL::HMAC.hexdigest(algorithm, @api_key.secret, data)
+    true_signature == @signature
+  end
+end