fix!: Use Viewtype::File for messages with invalid images, images of unknown size, images > 50 Mpx (#6825)

BREAKING CHANGE: messages with invalid images, images of unknown size,
huge images, will have Viewtype::File

After changing the logic of Viewtype selection, I had to fix 3 old tests
that used invalid Base64 image data.

Co-authored-by: iequidoo <117991069+iequidoo@users.noreply.github.com>

Cargo.lock

@@ -1367,6 +1367,7 @@ dependencies = [
  "tokio-tar",
  "tokio-util",
  "toml",
+ "tracing",
  "url",
  "uuid",
  "webpki-roots",

Cargo.toml

@@ -108,6 +108,7 @@ tokio-tar = { version = "0.3" } # TODO: integrate tokio into async-tar
 tokio-util = { workspace = true }
 tokio = { workspace = true, features = ["fs", "rt-multi-thread", "macros"] }
 toml = "0.8"
+tracing = "0.1.41"
 url = "2"
 uuid = { version = "1", features = ["serde", "v4"] }
 webpki-roots = "0.26.8"

src/accounts.rs

@@ -53,6 +53,14 @@ impl Accounts {
         Accounts::open(dir, writable).await
     }
 
+    /// Get the ID used to log events.
+    ///
+    /// Account manager logs events with ID 0
+    /// which is not used by any accounts.
+    fn get_id(&self) -> u32 {
+        0
+    }
+
     /// Creates a new default structure.
     async fn create(dir: &Path) -> Result<()> {
         fs::create_dir_all(dir)

src/constants.rs

@@ -223,6 +223,10 @@ pub(crate) const WORSE_AVATAR_BYTES: usize = 20_000; // this also fits to Outloo
 pub const BALANCED_IMAGE_SIZE: u32 = 1280;
 pub const WORSE_IMAGE_SIZE: u32 = 640;
 
+/// Limit for received images size. Bigger images become `Viewtype::File` to avoid excessive memory
+/// usage by UIs.
+pub const MAX_RCVD_IMAGE_PIXELS: u32 = 50_000_000;
+
 // Key for the folder configuration version (see below).
 pub(crate) const DC_FOLDERS_CONFIGURED_KEY: &str = "folders_configured";
 // this value can be increased if the folder configuration is changed and must be redone on next program start

src/log.rs

@@ -14,6 +14,7 @@ macro_rules! info {
                            file = file!(),
                            line = line!(),
                            msg = &formatted);
+        ::tracing::event!(::tracing::Level::INFO, account_id = $ctx.get_id(), "{}", &formatted);
         $ctx.emit_event($crate::EventType::Info(full));
     }};
 }
@@ -33,6 +34,7 @@ mod warn_macro_mod {
                                file = file!(),
                                line = line!(),
                                msg = &formatted);
+            ::tracing::event!(::tracing::Level::WARN, account_id = $ctx.get_id(), "{}", &formatted);
             $ctx.emit_event($crate::EventType::Warning(full));
         }};
     }
@@ -48,6 +50,7 @@ macro_rules! error {
     };
     ($ctx:expr, $msg:expr, $($args:expr),* $(,)?) => {{
         let formatted = format!($msg, $($args),*);
+        ::tracing::event!(::tracing::Level::ERROR, account_id = $ctx.get_id(), "{}", &formatted);
         $ctx.set_last_error(&formatted);
         $ctx.emit_event($crate::EventType::Error(formatted));
     }};
@@ -113,6 +116,12 @@ impl<T, E: std::fmt::Display> LogExt<T, E> for Result<T, E> {
             );
             // We can't use the warn!() macro here as the file!() and line!() macros
             // don't work with #[track_caller]
+            tracing::event!(
+                ::tracing::Level::WARN,
+                account_id = context.get_id(),
+                "{}",
+                &full
+            );
             context.emit_event(crate::EventType::Warning(full));
         };
         self

src/mimeparser.rs

@@ -1393,6 +1393,20 @@ impl MimeMessage {
             } else {
                 Viewtype::File
             }
+        } else if msg_type == Viewtype::Image
+            || msg_type == Viewtype::Gif
+            || msg_type == Viewtype::Sticker
+        {
+            match get_filemeta(decoded_data) {
+                // image size is known, not too big, keep msg_type:
+                Ok((width, height)) if width * height <= constants::MAX_RCVD_IMAGE_PIXELS => {
+                    part.param.set_i64(Param::Width, width.into());
+                    part.param.set_i64(Param::Height, height.into());
+                    msg_type
+                }
+                // image is too big or size is unknown, display as file:
+                _ => Viewtype::File,
+            }
         } else {
             msg_type
         };
@@ -1413,13 +1427,6 @@ impl MimeMessage {
             };
         info!(context, "added blobfile: {:?}", blob.as_name());
 
-        if mime_type.type_() == mime::IMAGE {
-            if let Ok((width, height)) = get_filemeta(decoded_data) {
-                part.param.set_int(Param::Width, width as i32);
-                part.param.set_int(Param::Height, height as i32);
-            }
-        }
-
         part.typ = msg_type;
         part.org_filename = Some(filename.to_string());
         part.mimetype = Some(mime_type);

src/mimeparser/mimeparser_tests.rs

@@ -835,15 +835,7 @@ Content-Transfer-Encoding: base64
 Content-Disposition: inline;
  filename="JPEG_filename.jpg"
 
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 ----11019878869865180--
@@ -908,15 +900,7 @@ Content-ID: <part1.9DFA679B.52A88D69@example.org>
 Content-Disposition: inline;
  filename="1.png"
 
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 --------------10CC6C2609EB38DA782C5CA9--
 
 --------------779C1631600DF3DB8C02E53A--"#;
@@ -979,15 +963,7 @@ Content-Type: image/jpeg;
 Content-Transfer-Encoding: base64
 Content-ID: <image001.jpg@01D622B3.C9D8D750>
 
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 ------=_NextPart_000_0003_01D622B3.CA753E60--
 "#;
@@ -2022,3 +1998,48 @@ async fn test_protected_date() -> Result<()> {
     assert_eq!(alice_msg.get_timestamp(), bob_msg.get_timestamp());
     Ok(())
 }
+
+#[tokio::test(flavor = "multi_thread", worker_threads = 2)]
+async fn test_huge_image_becomes_file() -> Result<()> {
+    let t = TestContext::new_alice().await;
+    let msg_id = receive_imf(
+        &t,
+        include_bytes!("../../test-data/message/image_huge_64M.eml"),
+        false,
+    )
+    .await?
+    .unwrap()
+    .msg_ids[0];
+    let msg = Message::load_from_db(&t.ctx, msg_id).await.unwrap();
+    // Huge image should be treated as file:
+    assert_eq!(msg.viewtype, Viewtype::File);
+    assert!(msg.get_file(&t).is_some());
+    assert_eq!(msg.get_filename().unwrap(), "huge_image.png");
+    assert_eq!(msg.get_filemime().unwrap(), "image/png");
+    // File has no width or height
+    assert!(msg.param.get_int(Param::Width).is_none());
+    assert!(msg.param.get_int(Param::Height).is_none());
+    Ok(())
+}
+
+#[tokio::test(flavor = "multi_thread", worker_threads = 2)]
+async fn test_4k_image_stays_image() -> Result<()> {
+    let t = TestContext::new_alice().await;
+    let msg_id = receive_imf(
+        &t,
+        include_bytes!("../../test-data/message/image_4k.eml"),
+        false,
+    )
+    .await?
+    .unwrap()
+    .msg_ids[0];
+    let msg = Message::load_from_db(&t.ctx, msg_id).await.unwrap();
+    // 4K image should be treated as image:
+    assert_eq!(msg.viewtype, Viewtype::Image);
+    assert!(msg.get_file(&t).is_some());
+    assert_eq!(msg.get_filename().unwrap(), "4k_image.png");
+    assert_eq!(msg.get_filemime().unwrap(), "image/png");
+    assert_eq!(msg.param.get_int(Param::Width).unwrap_or_default(), 3840);
+    assert_eq!(msg.param.get_int(Param::Height).unwrap_or_default(), 2160);
+    Ok(())
+}

src/receive_imf.rs

@@ -2899,17 +2899,17 @@ async fn apply_group_changes(
         }
     }
 
-    apply_chat_name_and_avatar_changes(
-        context,
-        mime_parser,
-        from_id,
-        chat,
-        &mut send_event_chat_modified,
-        &mut better_msg,
-    )
-    .await?;
-
     if is_from_in_chat {
+        apply_chat_name_and_avatar_changes(
+            context,
+            mime_parser,
+            from_id,
+            chat,
+            &mut send_event_chat_modified,
+            &mut better_msg,
+        )
+        .await?;
+
         if chat.member_list_is_stale(context).await? {
             info!(context, "Member list is stale.");
             let mut new_members: HashSet<ContactId> =

src/receive_imf/receive_imf_tests.rs

@@ -4212,14 +4212,18 @@ async fn test_keep_member_list_if_possibly_nomember() -> Result<()> {
     let fiona_chat_id = fiona.recv_msg(&alice.pop_sent_msg().await).await.chat_id;
     fiona_chat_id.accept(&fiona).await?;
 
-    send_text_msg(&fiona, fiona_chat_id, "hi".to_string()).await?;
+    SystemTime::shift(Duration::from_secs(60));
+    chat::set_chat_name(&fiona, fiona_chat_id, "Renamed").await?;
     bob.recv_msg(&fiona.pop_sent_msg().await).await;
 
-    // Bob missed the message adding fiona, but mustn't recreate the member list.
+    // Bob missed the message adding fiona, but mustn't recreate the member list or apply the group
+    // name change.
     assert_eq!(get_chat_contacts(&bob, bob_chat_id).await?.len(), 2);
     assert!(is_contact_in_chat(&bob, bob_chat_id, ContactId::SELF).await?);
     let bob_alice_contact = bob.add_or_lookup_contact_id(&alice).await;
     assert!(is_contact_in_chat(&bob, bob_chat_id, bob_alice_contact).await?);
+    let chat = Chat::load_from_db(&bob, bob_chat_id).await?;
+    assert_eq!(chat.get_name(), "Group");
     Ok(())
 }
 

src/sql/migrations.rs

@@ -2,7 +2,7 @@
 
 use std::collections::BTreeMap;
 use std::collections::BTreeSet;
-use std::time::{Duration, Instant};
+use std::time::Duration;
 
 use anyhow::{Context as _, Result, ensure};
 use deltachat_contact_tools::EmailAddress;
@@ -1237,13 +1237,13 @@ CREATE INDEX gossip_timestamp_index ON gossip_timestamp (chat_id, fingerprint);
 
     inc_and_check(&mut migration_version, 132)?;
     if dbversion < migration_version {
-        let start = Instant::now();
+        let start = Time::now();
         sql.execute_migration_transaction(|t| migrate_key_contacts(context, t), migration_version)
             .await?;
         info!(
             context,
             "key-contacts migration took {:?} in total.",
-            start.elapsed()
+            time_elapsed(&start),
         );
         // Schedule `msgs_to_key_contacts()`.
         context

src/tools.rs

@@ -14,7 +14,8 @@ use std::str::from_utf8;
 // `Instant` may use `libc::clock_gettime(CLOCK_MONOTONIC)`, e.g. on Android, and does not advance
 // while being in deep sleep mode, we use `SystemTime` instead, but add an alias for it to document
 // why `Instant` isn't used in those places. Also this can help to switch to another clock impl if
-// we find any.
+// we find any. Another reason is that `Instant` may reintroduce panics in the future versions:
+// https://doc.rust-lang.org/1.87.0/std/time/struct.Instant.html#method.elapsed.
 use std::time::Duration;
 pub use std::time::SystemTime as Time;
 #[cfg(not(test))]

test-data/message/image_4k.eml

@@ -0,0 +1,28 @@
+Received: (Postfix, from userid 1000); Mon, 4 Dec 2006 14:51:39 +0100 (CET)
+From: Test Sender <sender@testrun.org>
+Subject: Large image test
+To: alice@example.org
+Message-ID: <big-image-test@testrun.org>
+Date: Thu, 17 Dec 2020 15:38:45 +0100
+User-Agent: Test-Agent/1.0
+MIME-Version: 1.0
+Content-Type: multipart/mixed;
+ boundary="------------BIG_IMAGE_BOUNDARY"
+Content-Language: en-US
+
+This is a multi-part message in MIME format.
+--------------BIG_IMAGE_BOUNDARY
+Content-Type: text/plain; charset=utf-8
+Content-Transfer-Encoding: 7bit
+
+Here is a 4k image
+
+--------------BIG_IMAGE_BOUNDARY
+Content-Type: image/png;
+ name="4k_image.png"
+Content-Transfer-Encoding: base64
+Content-Disposition: attachment;
+ filename="4k_image.png"
+
+iVBORw0KGgoAAAANSUhEUgAADwAAAAhwCAIAAAAf3FwlAAAAEElEQVR4nAEFAPr/AP////8AAAAFCeiupAAAAABJRU5ErkJggg==
+--------------BIG_IMAGE_BOUNDARY--

test-data/message/image_huge_64M.eml

@@ -0,0 +1,28 @@
+Received: (Postfix, from userid 1000); Mon, 4 Dec 2006 14:51:39 +0100 (CET)
+From: Test Sender <sender@testrun.org>
+Subject: Large image test
+To: alice@example.org
+Message-ID: <huge-image-test@testrun.org>
+Date: Thu, 17 Dec 2020 15:38:45 +0100
+User-Agent: Test-Agent/1.0
+MIME-Version: 1.0
+Content-Type: multipart/mixed;
+ boundary="------------HUGE_IMAGE_BOUNDARY"
+Content-Language: en-US
+
+This is a multi-part message in MIME format.
+--------------HUGE_IMAGE_BOUNDARY
+Content-Type: text/plain; charset=utf-8
+Content-Transfer-Encoding: 7bit
+
+Here is a huge image
+
+--------------HUGE_IMAGE_BOUNDARY
+Content-Type: image/png;
+ name="huge_image.png"
+Content-Transfer-Encoding: base64
+Content-Disposition: attachment;
+ filename="huge_image.png"
+
+iVBORw0KGgoAAAANSUhEUgAAH0AAAB9ACAIAAACJkzqjAAAAEElEQVR4nAEFAPr/AP////8AAAAFCeiupAAAAABJRU5ErkJggg==
+--------------HUGE_IMAGE_BOUNDARY--