From 9784f2b53f84044d2d4aceb49e5234ce1bd674d7 Mon Sep 17 00:00:00 2001
From: Lennart <18233294+lennart-k@users.noreply.github.com>
Date: Wed, 31 Dec 2025 16:50:32 +0100
Subject: [PATCH] PUT object: Properly check If-None-Match header

---
 crates/caldav/src/calendar_object/methods.rs | 18 +++++++++++++++++-
 crates/carddav/src/address_object/methods.rs | 18 +++++++++++++++++-
 2 files changed, 34 insertions(+), 2 deletions(-)

diff --git a/crates/caldav/src/calendar_object/methods.rs b/crates/caldav/src/calendar_object/methods.rs
index e6fdb8a..7e475ac 100644
--- a/crates/caldav/src/calendar_object/methods.rs
+++ b/crates/caldav/src/calendar_object/methods.rs
@@ -73,7 +73,23 @@ pub async fn put_event<C: CalendarStore>(
     }
 
     let overwrite = if let Some(TypedHeader(if_none_match)) = if_none_match {
-        if_none_match == IfNoneMatch::any()
+        // TODO: Put into transaction?
+        let existing = match cal_store
+            .get_object(&principal, &calendar_id, &object_id, false)
+            .await
+        {
+            Ok(existing) => Some(existing),
+            Err(rustical_store::Error::NotFound) => None,
+            Err(err) => Err(err)?,
+        };
+        existing.is_none_or(|existing| {
+            if_none_match.precondition_passes(
+                &existing
+                    .get_etag()
+                    .parse()
+                    .expect("We only generate valid ETags"),
+            )
+        })
     } else {
         true
     };
diff --git a/crates/carddav/src/address_object/methods.rs b/crates/carddav/src/address_object/methods.rs
index 9520189..a93c78d 100644
--- a/crates/carddav/src/address_object/methods.rs
+++ b/crates/carddav/src/address_object/methods.rs
@@ -82,7 +82,23 @@ pub async fn put_object<AS: AddressbookStore>(
     }
 
     let overwrite = if let Some(TypedHeader(if_none_match)) = if_none_match {
-        if_none_match == IfNoneMatch::any()
+        // TODO: Put into transaction?
+        let existing = match addr_store
+            .get_object(&principal, &addressbook_id, &object_id, false)
+            .await
+        {
+            Ok(existing) => Some(existing),
+            Err(rustical_store::Error::NotFound) => None,
+            Err(err) => Err(err)?,
+        };
+        existing.is_none_or(|existing| {
+            if_none_match.precondition_passes(
+                &existing
+                    .get_etag()
+                    .parse()
+                    .expect("We only generate valid ETags"),
+            )
+        })
     } else {
         true
     };