Add SMTP reply for unrecognized commands

Signed-off-by: Mroik <mroik@delayed.space>

1 files changed, 9 insertions, 1 deletions

diff --git a/src/smtp.rs b/src/smtp.rs
index b77a0b6..6614897 100644
--- a/src/smtp.rs
+++ b/src/smtp.rs
@@ -61,7 +61,13 @@ impl SessionHandler {
             }
             log::debug!("Received '{}' from '{}'", buffer.trim(), self.addr);
 
-            let command = Command::try_from(buffer.as_str())?;
+            let command = match Command::try_from(buffer.as_str()) {
+                Err(_) => {
+                    writer.write_all(Reply::InvalidCommand.to_string().as_bytes())?;
+                    continue;
+                }
+                Ok(v) => v,
+            };
             let res = self.apply(command).await?;
             writer.write_all(res.to_string().as_bytes())?;
 
@@ -101,6 +107,7 @@ impl Default for SessionState {
 enum Reply {
     Ready(String),
     Completed(String),
+    InvalidCommand,
 }
 
 impl ToString for Reply {
@@ -108,6 +115,7 @@ impl ToString for Reply {
         match self {
             Reply::Ready(hostname) => format!("220 {}", hostname),
             Reply::Completed(hostname) => format!("250 {}", hostname),
+            Reply::InvalidCommand => format!("500 Command not recognized"),
         }
     }
 }