Split ForcePlaintext param into two booleans

This allows to send encrypted messages without Autocrypt header.

src/chat.rs

@@ -842,12 +842,10 @@ impl Chat {
             /* check if we want to encrypt this message.  If yes and circumstances change
             so that E2EE is no longer available at a later point (reset, changed settings),
             we might not send the message out at all */
-            if msg
+            if !msg
                 .param
-                .get_int(Param::ForcePlaintext)
-                .and_then::<ForcePlaintext, _>(num_traits::FromPrimitive::from_i32)
+                .get_bool(Param::ForcePlaintext)
                 .unwrap_or_default()
-                == ForcePlaintext::Dont
             {
                 let mut can_encrypt = true;
                 let mut all_mutual = context.get_config_bool(Config::E2eeEnabled).await;

src/imex.rs

@@ -220,10 +220,8 @@ async fn do_initiate_key_transfer(context: &Context) -> Result<String> {
     msg.param
         .set(Param::MimeType, "application/autocrypt-setup");
     msg.param.set_cmd(SystemMessage::AutocryptSetupMessage);
-    msg.param.set_int(
-        Param::ForcePlaintext,
-        ForcePlaintext::NoAutocryptHeader as i32,
-    );
+    msg.param.set_int(Param::ForcePlaintext, 1);
+    msg.param.set_int(Param::SkipAutocrypt, 1);
 
     let msg_id = chat::send_msg(context, chat_id, &mut msg).await?;
     info!(context, "Wait for setup message being sent ...",);

src/mimefactory.rs

@@ -237,23 +237,16 @@ impl<'a, 'b> MimeFactory<'a, 'b> {
                     return true;
                 }
 
-                let force_plaintext: ForcePlaintext = self
+                !self
                     .msg
                     .param
-                    .get_int(Param::ForcePlaintext)
-                    .and_then(num_traits::FromPrimitive::from_i32)
-                    .unwrap_or_default();
-
-                if force_plaintext == ForcePlaintext::Dont {
-                    return self
+                    .get_bool(Param::ForcePlaintext)
+                    .unwrap_or_default()
+                    && self
                         .msg
                         .param
-                        .get_int(Param::GuaranteeE2ee)
+                        .get_bool(Param::GuaranteeE2ee)
                         .unwrap_or_default()
-                        != 0;
-                }
-
-                false
             }
             Loaded::MDN { .. } => false,
         }
@@ -272,20 +265,30 @@ impl<'a, 'b> MimeFactory<'a, 'b> {
         }
     }
 
-    fn should_force_plaintext(&self) -> ForcePlaintext {
+    fn should_force_plaintext(&self) -> bool {
         match &self.loaded {
             Loaded::Message { chat } => {
                 if chat.typ == Chattype::VerifiedGroup {
-                    ForcePlaintext::Dont
+                    false
                 } else {
                     self.msg
                         .param
-                        .get_int(Param::ForcePlaintext)
-                        .and_then(num_traits::FromPrimitive::from_i32)
+                        .get_bool(Param::ForcePlaintext)
                         .unwrap_or_default()
                 }
             }
-            Loaded::MDN { .. } => ForcePlaintext::NoAutocryptHeader,
+            Loaded::MDN { .. } => true,
+        }
+    }
+
+    fn should_skip_autocrypt(&self) -> bool {
+        match &self.loaded {
+            Loaded::Message { .. } => self
+                .msg
+                .param
+                .get_bool(Param::SkipAutocrypt)
+                .unwrap_or_default(),
+            Loaded::MDN { .. } => true,
         }
     }
 
@@ -478,6 +481,7 @@ impl<'a, 'b> MimeFactory<'a, 'b> {
         let min_verified = self.min_verified();
         let grpimage = self.grpimage();
         let force_plaintext = self.should_force_plaintext();
+        let skip_autocrypt = self.should_skip_autocrypt();
         let subject_str = self.subject_str().await;
         let e2ee_guaranteed = self.is_e2ee_guaranteed();
         let encrypt_helper = EncryptHelper::new(self.context).await?;
@@ -501,7 +505,7 @@ impl<'a, 'b> MimeFactory<'a, 'b> {
             Loaded::MDN { .. } => self.render_mdn().await?,
         };
 
-        if force_plaintext != ForcePlaintext::NoAutocryptHeader {
+        if !skip_autocrypt {
             // unless determined otherwise we add the Autocrypt header
             let aheader = encrypt_helper.get_aheader().to_string();
             unprotected_headers.push(Header::new("Autocrypt".into(), aheader));
@@ -512,7 +516,7 @@ impl<'a, 'b> MimeFactory<'a, 'b> {
         let peerstates = self.peerstates_for_recipients().await?;
         let should_encrypt =
             encrypt_helper.should_encrypt(self.context, e2ee_guaranteed, &peerstates)?;
-        let is_encrypted = should_encrypt && force_plaintext == ForcePlaintext::Dont;
+        let is_encrypted = should_encrypt && !force_plaintext;
 
         let rfc724_mid = match self.loaded {
             Loaded::Message { .. } => self.msg.rfc724_mid.clone(),

src/param.rs

@@ -43,6 +43,9 @@ pub enum Param {
     /// For Messages: force unencrypted message, a value from `ForcePlaintext` enum.
     ForcePlaintext = b'u',
 
+    /// For Messages: do not include Autocrypt header.
+    SkipAutocrypt = b'o',
+
     /// For Messages
     WantsMdn = b'r',
 
@@ -127,32 +130,6 @@ pub enum Param {
     MsgId = b'I',
 }
 
-/// Possible values for `Param::ForcePlaintext`.
-#[derive(PartialEq, Eq, Debug, Clone, Copy, FromPrimitive)]
-#[repr(u8)]
-pub enum ForcePlaintext {
-    /// Do not force plaintext
-    Dont = 0,
-
-    /// Force plaintext message with Autocrypt header
-    ///
-    /// Used for `vc-request` and `vg-request` messages in
-    /// Verified Contact Protocol and
-    /// Verified Group Protocol.
-    AddAutocryptHeader = 1,
-
-    /// Force plaintext message without Autocrypt header
-    ///
-    /// Used for MDNs.
-    NoAutocryptHeader = 2,
-}
-
-impl Default for ForcePlaintext {
-    fn default() -> Self {
-        Self::Dont
-    }
-}
-
 /// An object for handling key=value parameter lists.
 ///
 /// The structure is serialized by calling `to_string()` on it.

src/securejoin.rs

@@ -409,10 +409,7 @@ async fn send_handshake_msg(
         msg.param.set(Param::Arg4, grpid.as_ref());
     }
     if step == "vg-request" || step == "vc-request" {
-        msg.param.set_int(
-            Param::ForcePlaintext,
-            ForcePlaintext::AddAutocryptHeader as i32,
-        );
+        msg.param.set_int(Param::ForcePlaintext, 1);
     } else {
         msg.param.set_int(Param::GuaranteeE2ee, 1);
     }