feat: Add broadcast QR type (todo: documentation)

deltachat-ffi/src/lot.rs

@@ -45,6 +45,7 @@ impl Lot {
             Self::Qr(qr) => match qr {
                 Qr::AskVerifyContact { .. } => None,
                 Qr::AskVerifyGroup { grpname, .. } => Some(Cow::Borrowed(grpname)),
+                Qr::AskJoinBroadcast { broadcast_name, .. } => Some(Cow::Borrowed(broadcast_name)),
                 Qr::FprOk { .. } => None,
                 Qr::FprMismatch { .. } => None,
                 Qr::FprWithoutAddr { fingerprint, .. } => Some(Cow::Borrowed(fingerprint)),
@@ -99,6 +100,7 @@ impl Lot {
             Self::Qr(qr) => match qr {
                 Qr::AskVerifyContact { .. } => LotState::QrAskVerifyContact,
                 Qr::AskVerifyGroup { .. } => LotState::QrAskVerifyGroup,
+                Qr::AskJoinBroadcast { .. } => LotState::QrAskJoinBroadcast,
                 Qr::FprOk { .. } => LotState::QrFprOk,
                 Qr::FprMismatch { .. } => LotState::QrFprMismatch,
                 Qr::FprWithoutAddr { .. } => LotState::QrFprWithoutAddr,
@@ -126,6 +128,7 @@ impl Lot {
             Self::Qr(qr) => match qr {
                 Qr::AskVerifyContact { contact_id, .. } => contact_id.to_u32(),
                 Qr::AskVerifyGroup { .. } => Default::default(),
+                Qr::AskJoinBroadcast { .. } => Default::default(),
                 Qr::FprOk { contact_id } => contact_id.to_u32(),
                 Qr::FprMismatch { contact_id } => contact_id.unwrap_or_default().to_u32(),
                 Qr::FprWithoutAddr { .. } => Default::default(),
@@ -169,6 +172,9 @@ pub enum LotState {
     /// text1=groupname
     QrAskVerifyGroup = 202,
 
+    /// text1=broadcast_name
+    QrAskJoinBroadcast = 204,
+
     /// id=contact
     QrFprOk = 210,
 

deltachat-jsonrpc/src/api/types/qr.rs

@@ -34,6 +34,21 @@ pub enum QrObject {
         /// Authentication code.
         authcode: String,
     },
+    /// Ask the user whether to join the broadcast channel.
+    AskJoinBroadcast {
+        /// Chat name.
+        broadcast_name: String,
+        /// Group ID.
+        grpid: String,
+        /// ID of the contact.
+        contact_id: u32,
+        /// Fingerprint of the contact key as scanned from the QR code.
+        fingerprint: String,
+
+        /// The secret shared between all members,
+        /// used to symmetrically encrypt&decrypt messages.
+        shared_secret: String,
+    },
     /// Contact fingerprint is verified.
     ///
     /// Ask the user if they want to start chatting.
@@ -207,6 +222,23 @@ impl From<Qr> for QrObject {
                     authcode,
                 }
             }
+            Qr::AskJoinBroadcast {
+                broadcast_name,
+                grpid,
+                contact_id,
+                fingerprint,
+                shared_secret,
+            } => {
+                let contact_id = contact_id.to_u32();
+                let fingerprint = fingerprint.to_string();
+                QrObject::AskJoinBroadcast {
+                    broadcast_name,
+                    grpid,
+                    contact_id,
+                    fingerprint,
+                    shared_secret,
+                }
+            }
             Qr::FprOk { contact_id } => {
                 let contact_id = contact_id.to_u32();
                 QrObject::FprOk { contact_id }

src/qr.rs

@@ -84,6 +84,21 @@ pub enum Qr {
         authcode: String,
     },
 
+    /// Ask whether to join the broadcast channel.
+    AskJoinBroadcast {
+        // TODO document
+        broadcast_name: String,
+
+        // TODO not sure wheter it makes sense to call this grpid just because it's called like this in the db
+        grpid: String,
+
+        contact_id: ContactId,
+
+        fingerprint: Fingerprint,
+
+        shared_secret: String,
+    },
+
     /// Contact fingerprint is verified.
     ///
     /// Ask the user if they want to start chatting.
@@ -381,7 +396,7 @@ pub fn format_backup(qr: &Qr) -> Result<String> {
 
 /// scheme: `OPENPGP4FPR:FINGERPRINT#a=ADDR&n=NAME&i=INVITENUMBER&s=AUTH`
 ///     or: `OPENPGP4FPR:FINGERPRINT#a=ADDR&g=GROUPNAME&x=GROUPID&i=INVITENUMBER&s=AUTH`
-///     or: `OPENPGP4FPR:FINGERPRINT#a=ADDR&c=CHANNELNAME&x=CHANNELID&s=SHAREDSECRET`
+///     or: `OPENPGP4FPR:FINGERPRINT#a=ADDR&g=BROADCAST_NAME&x=BROADCAST_ID&b=BROADCAST_SHARED_SECRET`
 ///     or: `OPENPGP4FPR:FINGERPRINT#a=ADDR`
 async fn decode_openpgp(context: &Context, qr: &str) -> Result<Qr> {
     let payload = qr
@@ -440,6 +455,10 @@ async fn decode_openpgp(context: &Context, qr: &str) -> Result<Qr> {
         .get("x")
         .filter(|&s| validate_id(s))
         .map(|s| s.to_string());
+    let broadcast_shared_secret = param
+        .get("b")
+        .filter(|&s| validate_id(s))
+        .map(|s| s.to_string());
 
     let grpname = if grpid.is_some() {
         if let Some(encoded_name) = param.get("g") {
@@ -526,6 +545,30 @@ async fn decode_openpgp(context: &Context, qr: &str) -> Result<Qr> {
                 authcode,
             })
         }
+    } else if let (Some(addr), Some(broadcast_name), Some(grpid), Some(shared_secret)) =
+        (&addr, grpname, grpid, broadcast_shared_secret)
+    {
+        // This is a broadcast channel invite link.
+        // TODO code duplication with the previous block
+        // TODO at some point, we can mark this person as verified
+        let addr = ContactAddress::new(addr)?;
+        let (contact_id, _) = Contact::add_or_lookup_ex(
+            context,
+            &name,
+            &addr,
+            &fingerprint.hex(),
+            Origin::UnhandledSecurejoinQrScan,
+        )
+        .await
+        .with_context(|| format!("failed to add or lookup contact for address {addr:?}"))?;
+
+        Ok(Qr::AskJoinBroadcast {
+            broadcast_name,
+            grpid,
+            contact_id,
+            fingerprint,
+            shared_secret,
+        })
     } else if let Some(addr) = addr {
         let fingerprint = fingerprint.hex();
         let (contact_id, _) =

src/securejoin/bob.rs

@@ -47,6 +47,7 @@ pub(super) async fn start_protocol(context: &Context, invite: QrInvite) -> Resul
     let hidden = match invite {
         QrInvite::Contact { .. } => Blocked::Not,
         QrInvite::Group { .. } => Blocked::Yes,
+        QrInvite::Broadcast { .. } => Blocked::Yes,
     };
     let chat_id = ChatId::create_for_contact_with_blocked(context, invite.contact_id(), hidden)
         .await
@@ -113,6 +114,7 @@ pub(super) async fn start_protocol(context: &Context, invite: QrInvite) -> Resul
             chat::add_info_msg(context, group_chat_id, &msg, time()).await?;
             Ok(group_chat_id)
         }
+        QrInvite::Broadcast { .. } => {}
         QrInvite::Contact { .. } => {
             // For setup-contact the BobState already ensured the 1:1 chat exists because it
             // uses it to send the handshake messages.

src/securejoin/qrinvite.rs

@@ -29,6 +29,13 @@ pub enum QrInvite {
         invitenumber: String,
         authcode: String,
     },
+    Broadcast {
+        broadcast_name: String,
+        grpid: String,
+        contact_id: ContactId,
+        fingerprint: Fingerprint,
+        shared_secret: String,
+    },
 }
 
 impl QrInvite {
@@ -95,6 +102,19 @@ impl TryFrom<Qr> for QrInvite {
                 invitenumber,
                 authcode,
             }),
+            Qr::AskJoinBroadcast {
+                broadcast_name,
+                grpid,
+                contact_id,
+                fingerprint,
+                shared_secret,
+            } => Ok(QrInvite::Broadcast {
+                broadcast_name,
+                grpid,
+                contact_id,
+                fingerprint,
+                shared_secret,
+            }),
             _ => bail!("Unsupported QR type"),
         }
     }