password max length prompt (#9248)

Signed-off-by: 21pages <sunboeasy@gmail.com>

src/flutter_ffi.rs

@@ -2282,6 +2282,10 @@ pub fn main_clear_trusted_devices() {
     clear_trusted_devices()
 }
 
+pub fn main_max_encrypt_len() -> SyncReturn<usize> {
+    SyncReturn(max_encrypt_len())
+}
+
 pub fn session_request_new_display_init_msgs(session_id: SessionID, display: usize) {
     if let Some(session) = sessions::get_session_by_session_id(&session_id) {
         session.request_init_msgs(display);

src/ipc.rs

@@ -928,16 +928,23 @@ pub fn set_permanent_password(v: String) -> ResultType<()> {
 pub fn set_unlock_pin(v: String, translate: bool) -> ResultType<()> {
     let v = v.trim().to_owned();
     let min_len = 4;
-    if !v.is_empty() && v.len() < min_len {
-        let err = if translate {
-            crate::lang::translate(
-                "Requires at least {".to_string() + &format!("{min_len}") + "} characters",
-            )
-        } else {
-            // Sometimes, translated can't show normally in command line
-            format!("Requires at least {} characters", min_len)
-        };
-        bail!(err);
+    let max_len = crate::ui_interface::max_encrypt_len();
+    let len = v.chars().count();
+    if !v.is_empty() {
+        if len < min_len {
+            let err = if translate {
+                crate::lang::translate(
+                    "Requires at least {".to_string() + &format!("{min_len}") + "} characters",
+                )
+            } else {
+                // Sometimes, translated can't show normally in command line
+                format!("Requires at least {} characters", min_len)
+            };
+            bail!(err);
+        }
+        if len > max_len {
+            bail!("No more than {max_len} characters");
+        }
     }
     Config::set_unlock_pin(&v);
     set_config("unlock-pin", v)

src/ui_interface.rs

@@ -1495,3 +1495,8 @@ pub fn clear_trusted_devices() {
     #[cfg(not(any(target_os = "android", target_os = "ios")))]
     ipc::clear_trusted_devices();
 }
+
+#[cfg(feature = "flutter")]
+pub fn max_encrypt_len() -> usize {
+    hbb_common::config::ENCRYPT_MAX_LEN
+}