implement handling commands

src/main.rs

@@ -67,6 +67,7 @@ impl server::Server for Server {
             .unwrap();
         Handler {
             file,
+            buffer: vec![],
             user: "root".into(),
         }
     }
@@ -79,6 +80,7 @@ fn send_str(session: &mut Session, channel: ChannelId, s: String) {
 
 struct Handler {
     file: File,
+    buffer: Vec<u8>,
     user: String,
 }
 
@@ -86,6 +88,31 @@ impl Handler {
     fn send_prompt(&self, session: &mut Session, channel: ChannelId) {
         send_str(session, channel, format!("{}@fnordister:~$ ", self.user));
     }
+
+    fn handle_command<F: FnMut(&str)>(&self, command: String, mut respond: F) {
+        dbg!(&command);
+        let program_len = command.find(|c: char| c.is_whitespace())
+            .unwrap_or(command.len());
+        let program = &command[..program_len];
+
+        dbg!(program);
+        match program {
+            "whoami" => respond(&self.user),
+            "id" => respond(&format!("uid=0({}) gid=0(root)", self.user)),
+            "uname" => respond("Linux fnordister 5.10.0-10-amd64 #1 SMP Debian 5.10.84-1 (2021-12-08) x86_64 GNU/Linux"),
+            "pwd" => respond("/"),
+            "ls" => {
+                respond("drwxr-xr-x  18 root root    18 Jan  4  1969 .");
+                respond("drwxr-xr-x  18 root root    18 Jan  4  1969 ..");
+                respond("drwxr-xr-x  18 root root    18 Jan  4  0000 ...");
+            },
+            "bash" => {}
+            "sh" => {}
+            "cd" => {}
+            "" => {}
+            _ => respond(&format!("{}: command not found", program)),
+        }
+    }
 }
 
 impl server::Handler for Handler {
@@ -121,6 +148,14 @@ impl server::Handler for Handler {
         writeln!(self.file, "Execute: {}\n", String::from_utf8_lossy(data))
             .unwrap();
 
+        let line = String::from_utf8_lossy(data).into();
+        self.handle_command(line, |response| {
+            let mut data = Vec::from(response);
+            data.extend_from_slice(b"\r\n");
+            session.data(channel, data.into());
+        });
+        session.close(channel);
+
         self.finished(session)
     }
 
@@ -149,12 +184,24 @@ impl server::Handler for Handler {
             .unwrap();
         // echo input back
         session.data(channel, data.to_vec().into());
-        // pressed return?
-        if data.contains(&b'\r') {
-            writeln!(self.file).unwrap();
+
+        if self.buffer.len() < 1024 {
+            self.buffer.extend_from_slice(data);
+        }
+        if let Some(newline) = self.buffer.iter().position(|b| *b == b'\r') {
+            let rest = self.buffer.split_off(newline + 1);
+            let line: String = String::from_utf8_lossy(&self.buffer).into();
+            self.buffer = rest;
+
             session.data(channel, b"\n".to_vec().into());
+            self.handle_command(line, |response| {
+                let mut data = Vec::from(response);
+                data.extend_from_slice(b"\r\n");
+                session.data(channel, data.into());
+            });
             self.send_prompt(&mut session, channel);
         }
+
         self.finished(session)
     }
 }