From b5571fcc5b296f6d4f7b690dbf4c90bff61bbe12 Mon Sep 17 00:00:00 2001
From: Chili Palmer <hugoms@me.com>
Date: Wed, 12 Aug 2026 20:11:05 +0200
Subject: [PATCH] Treat PIN fields as sensitive (#81)

---
 crates/storage/src/document.rs          |  6 +++-
 crates/storage/src/mobile_entry.rs      |  5 +--
 crates/storage/tests/entry_documents.rs | 47 +++++++++++++++++++++++++
 3 files changed, 53 insertions(+), 5 deletions(-)

diff --git a/crates/storage/src/document.rs b/crates/storage/src/document.rs
index 37a945f..4cf3b44 100644
--- a/crates/storage/src/document.rs
+++ b/crates/storage/src/document.rs
@@ -684,7 +684,11 @@ fn classify(index: usize, line: &[u8]) -> EntryFieldMetadata {
         let kind = semantic_field_kind(name);
         return EntryFieldMetadata {
             kind,
-            sensitivity: EntrySensitivity::Ordinary,
+            sensitivity: if name.eq_ignore_ascii_case("pin") {
+                EntrySensitivity::Sensitive
+            } else {
+                EntrySensitivity::Ordinary
+            },
             name: Some(name.to_owned()),
             otp: None,
             diagnostic: std::str::from_utf8(&line[value_start..])
diff --git a/crates/storage/src/mobile_entry.rs b/crates/storage/src/mobile_entry.rs
index 03feb27..93ecd9c 100644
--- a/crates/storage/src/mobile_entry.rs
+++ b/crates/storage/src/mobile_entry.rs
@@ -575,10 +575,7 @@ fn editor_field(index: usize, field: &EntryField) -> MobileEntryEditorField {
             | EntryFieldKind::Field => MobileEntryEditorFieldKind::Field,
         }
     };
-    let sensitive = matches!(
-        kind,
-        MobileEntryEditorFieldKind::Password | MobileEntryEditorFieldKind::OtpUri
-    );
+    let sensitive = metadata.sensitivity() == EntrySensitivity::Sensitive;
     MobileEntryEditorField {
         id: field.id().value(),
         kind,
diff --git a/crates/storage/tests/entry_documents.rs b/crates/storage/tests/entry_documents.rs
index 10c967e..759fea3 100644
--- a/crates/storage/tests/entry_documents.rs
+++ b/crates/storage/tests/entry_documents.rs
@@ -277,6 +277,53 @@ fn mobile_projection_marks_an_empty_first_line_without_a_reveal_control() -> Tes
     Ok(())
 }
 
+#[test]
+fn pin_fields_are_sensitive_case_insensitively() -> TestResult {
+    let fixture = FixtureSet::load()?;
+    let store = fixture.materialize_store("basic")?;
+    let repository = Repository::open(store.path())?;
+    let keys = KeyStore::load(fixture.path("keys"))?;
+    let mut secrets = FixtureSecrets::all(&fixture);
+    write_plaintext(
+        &repository,
+        &keys,
+        "documents/pins",
+        b"password\nPIN: 1234\npin: 5678\nPiN: 9012\n",
+    )?;
+
+    let document =
+        EntryDocumentService::new(&repository, &keys).open("documents/pins", &mut secrets)?;
+    let pins = &document.fields()[1..];
+    assert!(pins.iter().all(|field| {
+        field.metadata().kind() == EntryFieldKind::Field
+            && field.metadata().sensitivity() == EntrySensitivity::Sensitive
+    }));
+
+    let page = MobileEntryPage::from_document(&document);
+    let projected = page
+        .sections()
+        .iter()
+        .flat_map(|section| section.fields())
+        .filter(|field| field.id() != 0)
+        .collect::<Vec<_>>();
+    assert_eq!(projected.len(), 3);
+    assert!(projected.iter().all(|field| {
+        field.sensitive()
+            && field.value().is_none()
+            && field.masked_value() == "Hidden"
+            && !field.selectable()
+    }));
+    assert_eq!(field_value(&document, pins[0].id().value())?, "1234");
+
+    let editor = MobileEntryDraft::new(document, false).page();
+    assert!(
+        editor.fields()[1..]
+            .iter()
+            .all(|field| field.sensitive() && field.masked_value() == "Hidden")
+    );
+    Ok(())
+}
+
 #[test]
 fn named_multiline_fields_are_one_lossless_logical_field() -> TestResult {
     let fixture = FixtureSet::load()?;