add basic dialog authentication

sqlx-mysql/src/protocol/auth_plugin.rs

@@ -8,11 +8,13 @@ use sqlx_core::{Error, Result};
 use crate::MySqlDatabaseError;
 
 mod caching_sha2;
+mod dialog;
 mod native;
 mod rsa;
 mod sha256;
 
 pub(crate) use self::caching_sha2::CachingSha2AuthPlugin;
+pub(crate) use self::dialog::DialogAuthPlugin;
 pub(crate) use self::native::NativeAuthPlugin;
 pub(crate) use self::sha256::Sha256AuthPlugin;
 
@@ -39,6 +41,7 @@ impl dyn AuthPlugin {
             _ if s == CachingSha2AuthPlugin.name() => Ok(Box::new(CachingSha2AuthPlugin)),
             _ if s == Sha256AuthPlugin.name() => Ok(Box::new(Sha256AuthPlugin)),
             _ if s == NativeAuthPlugin.name() => Ok(Box::new(NativeAuthPlugin)),
+            _ if s == DialogAuthPlugin.name() => Ok(Box::new(DialogAuthPlugin)),
 
             _ => Err(MySqlDatabaseError::new(
                 2059,
@@ -63,7 +66,8 @@ fn err_msg(plugin: &'static str, message: &str) -> Error {
     MySqlDatabaseError::new(
         2061,
         &format!("Authentication plugin '{}' reported error: {}", plugin, message),
-    ).into()
+    )
+    .into()
 }
 
 fn err<E>(plugin: &'static str, error: &E) -> Error

sqlx-mysql/src/protocol/auth_plugin/dialog.rs

@@ -0,0 +1,33 @@
+use bytes::buf::Chain;
+use bytes::Bytes;
+use sqlx_core::{Error, Result};
+use std::borrow::Cow;
+
+/// Dialog authentication implementation
+///
+/// https://mariadb.com/kb/en/authentication-plugin-pam/#dialog
+///
+#[derive(Debug)]
+pub(crate) struct DialogAuthPlugin;
+
+impl super::AuthPlugin for DialogAuthPlugin {
+    fn name(&self) -> &'static str {
+        "dialog"
+    }
+
+    fn invoke(&self, _nonce: &Chain<Bytes, Bytes>, password: &str) -> Vec<u8> {
+        password.as_bytes().to_vec()
+    }
+
+    fn handle(
+        &self,
+        _data: Bytes,
+        _nonce: &Chain<Bytes, Bytes>,
+        _password: &str,
+    ) -> Result<Option<Vec<u8>>> {
+        Err(Error::ConnectOptions {
+            message: Cow::Borrowed("interactive dialog authentication is currently not supported"),
+            source: None,
+        })
+    }
+}