SAK-33684 Handle SMTP FROM that isn’t email better (sakaiproject#5080)

Have better handling of a client attempting to send an email where the FROM address isn’t an email address that we can parse. This may be because it’s empty or it’s not an email address.

mailarchive/mailarchive-subetha/src/java/org/sakaiproject/mailarchive/SakaiMessageHandlerFactory.java

@@ -183,8 +183,13 @@ public MessageHandler create(MessageContext ctx) {
 
             @Override
             public void from(String from) throws RejectException {
-                SplitEmailAddress address = SplitEmailAddress.parse(from);
-                this.from = address.getLocal() + "@" + address.getDomain();
+                try {
+                    SplitEmailAddress address = SplitEmailAddress.parse(from);
+                    this.from = address.getLocal() + "@" + address.getDomain();
+                } catch (IllegalArgumentException iae) {
+                    log.debug("Not allowing return path of: {}", from);
+                    throw new RejectException("Not allowing return path of: "+ from);
+                }
             }
 
             @Override

mailarchive/mailarchive-subetha/src/java/org/sakaiproject/mailarchive/SplitEmailAddress.java

@@ -57,7 +57,7 @@ public String getDomain() {
     public static SplitEmailAddress parse(String address) {
         int atPos = address.indexOf('@');
         if (atPos < 1 || atPos == address.length() -1) {
-            throw new IllegalArgumentException("Can't find @ or it's at the start or end.");
+            throw new IllegalArgumentException("Can't find @ or it's at the start or end of: "+ address);
         }
         String local = address.substring(0, atPos);
         Matcher rfcMatcher = BATV_RFC.matcher(local);

mailarchive/mailarchive-subetha/src/test/org/sakaiproject/mailarchive/SakaiMessageHandlerTest.java

@@ -287,6 +287,22 @@ public void testNoPermission() throws Exception {
         writeData(client, "/no-permission.txt");
     }
 
+    @Test(expected = SMTPException.class)
+    public void testNoReturnPath() throws Exception {
+        // Here there isn't a good email in the from address to make a return path
+        String reference = "/mailarchive/no-good-mail/main";
+        SmartClient client = createClient();
+        client.from("");
+    }
+
+    @Test(expected = SMTPException.class)
+    public void testEmptyReturnPath() throws Exception {
+        // Here there isn't a good email in the from address to make a return path
+        String reference = "/mailarchive/empty-return-path/main";
+        SmartClient client = createClient();
+        client.from("");
+    }
+
     @Test
     public void testPostmaster() throws Exception {
         // Here there is no postmaster which may happen and should be dealt with