chore(tests): Add a way to disable DKIM for tests (#50)

Signed-off-by: Jagoda Ślązak <jslazak@jslazak.com>

filtermail/src/inbound.rs

@@ -15,13 +15,15 @@ use std::str::FromStr;
 pub struct IncomingBeforeQueueHandler {
     config: Config,
     dkim_verifier: DkimVerifier,
+    skip_dkim: bool,
 }
 
 impl IncomingBeforeQueueHandler {
-    pub fn new(config: Config) -> Result<Self, crate::error::Error> {
+    pub fn new(config: Config, skip_dkim: bool) -> Result<Self, crate::error::Error> {
         Ok(Self {
             config,
             dkim_verifier: DkimVerifier::new()?,
+            skip_dkim,
         })
     }
 }
@@ -67,9 +69,11 @@ impl SmtpHandler for IncomingBeforeQueueHandler {
                 }
             }
             AddressDomain::Name(domain) => {
+                if !self.skip_dkim {
                     self.dkim_verifier.verify(&envelope.data, &domain).await?;
                 }
             }
+        }
 
         let mail_encrypted = check_encrypted(&message, false);
         log::debug!("mail_encrypted: {mail_encrypted}");

filtermail/src/main.rs

@@ -96,9 +96,18 @@ async fn main() {
             process::exit(1);
         }
     } else {
+        // Skip DKIM verification (used for tests).
+        let skip_dkim = env::var("FILTERMAIL_SKIP_DKIM")
+            .map(|val| val == "1" || val.eq_ignore_ascii_case("true"))
+            .unwrap_or(false);
+
+        if skip_dkim {
+            log::warn!("DKIM verification DISABLED! This should not be used in production.");
+        }
+
         let handler = Arc::new(
             // We want to panic here if the handler cannot be created.
-            IncomingBeforeQueueHandler::new(config.clone()).unwrap(),
+            IncomingBeforeQueueHandler::new(config.clone(), skip_dkim).unwrap(),
         );
         let addr = format!("127.0.0.1:{}", config.filtermail_smtp_port_incoming);
         let max_size = config.max_message_size;