feat: ephemeral peer channels (#5346)

Co-authored-by: link2xt <link2xt@testrun.org>
Co-authored-by: iequidoo <117991069+iequidoo@users.noreply.github.com>

.gitignore

@@ -34,7 +34,6 @@ deltachat-ffi/xml
 coverage/
 .DS_Store
 .vscode
-.vscode/launch.json
 python/accounts.txt
 python/all-testaccounts.txt
 tmp/

Cargo.toml

@@ -60,7 +60,10 @@ hex = "0.4.0"
 hickory-resolver = "0.24"
 humansize = "2"
 image = { version = "0.25.1", default-features=false, features = ["gif", "jpeg", "ico", "png", "pnm", "webp", "bmp"] }
-iroh = { version = "0.4.2", default-features = false }
+iroh_old = { version = "0.4.2", default-features = false, package = "iroh"}
+iroh-net = "0.16.2"
+iroh-gossip = { version = "0.16.2", features = ["net"] }
+quinn = "0.10.0"
 kamadak-exif = "0.5.3"
 lettre_email = { git = "https://github.com/deltachat/lettre", branch = "master" }
 libc = "0.2"
@@ -79,7 +82,7 @@ quick-xml = "0.31"
 quoted_printable = "0.5"
 rand = "0.8"
 regex = { workspace = true }
-reqwest = { version = "0.12.2", features = ["json"] }
+reqwest = { version = "0.11.27", features = ["json"] }
 rusqlite = { workspace = true, features = ["sqlcipher"] }
 rust-hsluv = "0.1"
 sanitize-filename = "0.5"
@@ -178,4 +181,4 @@ vendored = [
   "async-native-tls/vendored",
   "rusqlite/bundled-sqlcipher-vendored-openssl",
   "reqwest/native-tls-vendored"
-]
+]

benches/contacts.rs

@@ -1,3 +1,4 @@
+#![recursion_limit = "256"]
 use criterion::{black_box, criterion_group, criterion_main, Criterion};
 use deltachat::contact::Contact;
 use deltachat::context::Context;

benches/create_account.rs

@@ -1,3 +1,4 @@
+#![recursion_limit = "256"]
 use std::path::PathBuf;
 
 use criterion::{black_box, criterion_group, criterion_main, Criterion};

benches/get_chat_msgs.rs

@@ -1,3 +1,4 @@
+#![recursion_limit = "256"]
 use std::path::Path;
 
 use criterion::{black_box, criterion_group, criterion_main, Criterion};

benches/get_chatlist.rs

@@ -1,3 +1,4 @@
+#![recursion_limit = "256"]
 use std::path::Path;
 
 use criterion::{black_box, criterion_group, criterion_main, Criterion};

benches/receive_emails.rs

@@ -1,3 +1,4 @@
+#![recursion_limit = "256"]
 use std::path::PathBuf;
 
 use criterion::{black_box, criterion_group, criterion_main, Criterion};

benches/search_msgs.rs

@@ -1,3 +1,4 @@
+#![recursion_limit = "256"]
 use std::path::Path;
 
 use criterion::{black_box, criterion_group, criterion_main, Criterion};

benches/send_events.rs

@@ -1,3 +1,4 @@
+#![recursion_limit = "256"]
 use criterion::{criterion_group, criterion_main, Criterion};
 
 use deltachat::context::Context;

deltachat-ffi/src/lib.rs

@@ -1,3 +1,4 @@
+#![recursion_limit = "256"]
 #![warn(unused, clippy::all)]
 #![allow(
     non_camel_case_types,
@@ -561,6 +562,7 @@ pub unsafe extern "C" fn dc_event_get_id(event: *mut dc_event_t) -> libc::c_int
         EventType::ConfigSynced { .. } => 2111,
         EventType::WebxdcStatusUpdate { .. } => 2120,
         EventType::WebxdcInstanceDeleted { .. } => 2121,
+        EventType::WebxdcRealtimeData { .. } => 2150,
         EventType::AccountsBackgroundFetchDone => 2200,
         EventType::ChatlistChanged => 2300,
         EventType::ChatlistItemChanged { .. } => 2301,
@@ -616,8 +618,9 @@ pub unsafe extern "C" fn dc_event_get_data1_int(event: *mut dc_event_t) -> libc:
         | EventType::SecurejoinJoinerProgress { contact_id, .. } => {
             contact_id.to_u32() as libc::c_int
         }
-        EventType::WebxdcStatusUpdate { msg_id, .. } => msg_id.to_u32() as libc::c_int,
+        EventType::WebxdcRealtimeData { msg_id, .. }
-        EventType::WebxdcInstanceDeleted { msg_id, .. } => msg_id.to_u32() as libc::c_int,
+        | EventType::WebxdcStatusUpdate { msg_id, .. }
+        | EventType::WebxdcInstanceDeleted { msg_id, .. } => msg_id.to_u32() as libc::c_int,
         EventType::ChatlistItemChanged { chat_id } => {
             chat_id.unwrap_or_default().to_u32() as libc::c_int
         }
@@ -655,6 +658,7 @@ pub unsafe extern "C" fn dc_event_get_data2_int(event: *mut dc_event_t) -> libc:
         | EventType::ConnectivityChanged
         | EventType::WebxdcInstanceDeleted { .. }
         | EventType::IncomingMsgBunch { .. }
+        | EventType::WebxdcRealtimeData { .. }
         | EventType::SelfavatarChanged
         | EventType::AccountsBackgroundFetchDone
         | EventType::ChatlistChanged
@@ -721,6 +725,7 @@ pub unsafe extern "C" fn dc_event_get_data2_str(event: *mut dc_event_t) -> *mut
         | EventType::SelfavatarChanged
         | EventType::WebxdcStatusUpdate { .. }
         | EventType::WebxdcInstanceDeleted { .. }
+        | EventType::WebxdcRealtimeData { .. }
         | EventType::AccountsBackgroundFetchDone
         | EventType::ChatEphemeralTimerModified { .. }
         | EventType::IncomingMsgBunch { .. }

deltachat-jsonrpc/src/api.rs

@@ -18,12 +18,14 @@ use deltachat::constants::DC_MSG_ID_DAYMARKER;
 use deltachat::contact::{may_be_valid_addr, Contact, ContactId, Origin};
 use deltachat::context::get_info;
 use deltachat::ephemeral::Timer;
-use deltachat::imex;
 use deltachat::location;
 use deltachat::message::get_msg_read_receipts;
 use deltachat::message::{
     self, delete_msgs, markseen_msgs, Message, MessageState, MsgId, Viewtype,
 };
+use deltachat::peer_channels::{
+    leave_webxdc_realtime, send_webxdc_realtime_advertisement, send_webxdc_realtime_data,
+};
 use deltachat::provider::get_provider_info;
 use deltachat::qr::{self, Qr};
 use deltachat::qr_code_generator::{generate_backup_qr, get_securejoin_qr_svg};
@@ -32,6 +34,7 @@ use deltachat::securejoin;
 use deltachat::stock_str::StockMessage;
 use deltachat::webxdc::StatusUpdateSerial;
 use deltachat::EventEmitter;
+use deltachat::{imex, info};
 use sanitize_filename::is_sanitized;
 use tokio::fs;
 use tokio::sync::{watch, Mutex, RwLock};
@@ -1763,6 +1766,37 @@ impl CommandApi {
             .await
     }
 
+    async fn send_webxdc_realtime_data(
+        &self,
+        account_id: u32,
+        instance_msg_id: u32,
+        data: Vec<u8>,
+    ) -> Result<()> {
+        let ctx = self.get_context(account_id).await?;
+        send_webxdc_realtime_data(&ctx, MsgId::new(instance_msg_id), data).await
+    }
+
+    async fn send_webxdc_realtime_advertisement(
+        &self,
+        account_id: u32,
+        instance_msg_id: u32,
+    ) -> Result<()> {
+        let ctx = self.get_context(account_id).await?;
+        let fut = send_webxdc_realtime_advertisement(&ctx, MsgId::new(instance_msg_id)).await?;
+        if let Some(fut) = fut {
+            tokio::spawn(async move {
+                fut.await.ok();
+                info!(ctx, "send_webxdc_realtime_advertisement done")
+            });
+        }
+        Ok(())
+    }
+
+    async fn leave_webxdc_realtime(&self, account_id: u32, instance_message_id: u32) -> Result<()> {
+        let ctx = self.get_context(account_id).await?;
+        leave_webxdc_realtime(&ctx, MsgId::new(instance_message_id)).await
+    }
+
     async fn get_webxdc_status_updates(
         &self,
         account_id: u32,

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

@@ -240,6 +240,10 @@ pub enum EventType {
         status_update_serial: u32,
     },
 
+    /// Data received over an ephemeral peer channel.
+    #[serde(rename_all = "camelCase")]
+    WebxdcRealtimeData { msg_id: u32, data: Vec<u8> },
+
     /// Inform that a message containing a webxdc instance has been deleted
     #[serde(rename_all = "camelCase")]
     WebxdcInstanceDeleted { msg_id: u32 },
@@ -362,6 +366,10 @@ impl From<CoreEventType> for EventType {
                 msg_id: msg_id.to_u32(),
                 status_update_serial: status_update_serial.to_u32(),
             },
+            CoreEventType::WebxdcRealtimeData { msg_id, data } => WebxdcRealtimeData {
+                msg_id: msg_id.to_u32(),
+                data,
+            },
             CoreEventType::WebxdcInstanceDeleted { msg_id } => WebxdcInstanceDeleted {
                 msg_id: msg_id.to_u32(),
             },

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

@@ -379,6 +379,9 @@ pub enum SystemMessageType {
 
     /// Webxdc info added with `info` set in `send_webxdc_status_update()`.
     WebxdcInfoMessage,
+
+    /// This message contains a users iroh node address.
+    IrohNodeAddr,
 }
 
 impl From<deltachat::mimeparser::SystemMessage> for SystemMessageType {
@@ -401,6 +404,7 @@ impl From<deltachat::mimeparser::SystemMessage> for SystemMessageType {
             SystemMessage::WebxdcStatusUpdate => SystemMessageType::WebxdcStatusUpdate,
             SystemMessage::WebxdcInfoMessage => SystemMessageType::WebxdcInfoMessage,
             SystemMessage::InvalidUnencryptedMail => SystemMessageType::InvalidUnencryptedMail,
+            SystemMessage::IrohNodeAddr => SystemMessageType::IrohNodeAddr,
             SystemMessage::SecurejoinWait => SystemMessageType::SecurejoinWait,
             SystemMessage::SecurejoinWaitTimeout => SystemMessageType::SecurejoinWaitTimeout,
         }

deltachat-jsonrpc/src/lib.rs

@@ -1,3 +1,4 @@
+#![recursion_limit = "256"]
 pub mod api;
 pub use yerpc;
 

deltachat-jsonrpc/src/webserver.rs

@@ -1,3 +1,4 @@
+#![recursion_limit = "256"]
 use std::net::SocketAddr;
 use std::path::PathBuf;
 

deltachat-repl/src/main.rs

@@ -1,3 +1,4 @@
+#![recursion_limit = "256"]
 //! This is a CLI program and a little testing frame.  This file must not be
 //! included when using Delta Chat Core as a library.
 //!

deltachat-rpc-server/src/main.rs

@@ -1,3 +1,4 @@
+#![recursion_limit = "256"]
 //! Delta Chat core RPC server.
 //!
 //! It speaks JSON Lines over stdio.

deny.toml

@@ -23,6 +23,9 @@ ignore = [
 # when upgrading.
 # Please keep this list alphabetically sorted.
 skip = [
+     { name = "asn1-rs-derive", version = "0.4.0" },
+     { name = "asn1-rs-impl", version = "0.1.0" },
+     { name = "asn1-rs", version = "0.5.2" },
      { name = "async-channel", version = "1.9.0" },
      { name = "base16ct", version = "0.1.1" },
      { name = "base64", version = "<0.21" },
@@ -34,20 +37,38 @@ skip = [
      { name = "darling_core", version = "<0.14" },
      { name = "darling_macro", version = "<0.14" },
      { name = "darling", version = "<0.14" },
+     { name = "der_derive", version = "0.6.1" },
+     { name = "derive_more", version = "0.99.17" },
+     { name = "der-parser", version = "8.2.0" },
      { name = "der", version = "0.6.1" },
      { name = "digest", version = "<0.10" },
+     { name = "dlopen2", version = "0.4.1" },
      { name = "ed25519-dalek", version = "1.0.1" },
      { name = "ed25519", version = "1.5.3" },
      { name = "env_logger", version = "0.10.2" },
      { name = "event-listener", version = "2.5.3" },
+     { name = "event-listener", version = "4.0.3" },
+     { name = "fastrand", version = "1.9.0" },
+     { name = "futures-lite", version = "1.13.0" },
      { name = "getrandom", version = "<0.2" },
+     { name = "http-body", version = "0.4.6" },
+     { name = "http", version = "0.2.12" },
+     { name = "hyper", version = "0.14.28" },
      { name = "idna", version = "0.4.0" },
+     { name = "netlink-packet-core", version = "0.5.0" },
+     { name = "netlink-packet-route", version = "0.15.0" },
+     { name = "nix", version = "0.26.4" },
+     { name = "oid-registry", version = "0.6.1" },
      { name = "pem-rfc7468", version = "0.6.0" },
+     { name = "pem", version = "1.1.1" },
      { name = "pkcs8", version = "0.9.0" },
+     { name = "proc-macro-error-attr", version = "0.4.12" },
+     { name = "proc-macro-error", version = "0.4.12" },
      { name = "quick-error", version = "<2.0" },
      { name = "rand_chacha", version = "<0.3" },
      { name = "rand_core", version = "<0.6" },
      { name = "rand", version = "<0.8" },
+     { name = "rcgen", version = "<0.12.1" },
      { name = "redox_syscall", version = "0.3.5" },
      { name = "regex-automata", version = "0.1.10" },
      { name = "regex-syntax", version = "0.6.29" },
@@ -57,23 +78,31 @@ skip = [
      { name = "signature", version = "1.6.4" },
      { name = "spin", version = "<0.9.6" },
      { name = "spki", version = "0.6.0" },
+     { name = "ssh-encoding", version = "0.1.0" },
+     { name = "ssh-key", version = "0.5.1" },
      { name = "sync_wrapper", version = "0.1.2" },
+     { name = "synstructure", version = "0.12.6" },
      { name = "syn", version = "1.0.109" },
+     { name = "system-configuration-sys", version = "0.5.0" },
+     { name = "system-configuration", version = "0.5.1" },
      { name = "time", version = "<0.3" },
      { name = "toml_edit", version = "0.21.1" },
      { name = "untrusted", version = "0.7.1" },
      { name = "wasi", version = "<0.11" },
      { name = "windows_aarch64_gnullvm", version = "<0.52" },
      { name = "windows_aarch64_msvc", version = "<0.52" },
+     { name = "windows-core", version = "<0.54.0" },
      { name = "windows_i686_gnu", version = "<0.52" },
      { name = "windows_i686_msvc", version = "<0.52" },
      { name = "windows-sys", version = "<0.52" },
      { name = "windows-targets", version = "<0.52" },
      { name = "windows", version = "0.32.0" },
+     { name = "windows", version = "<0.54.0" },
      { name = "windows_x86_64_gnullvm", version = "<0.52" },
      { name = "windows_x86_64_gnu", version = "<0.52" },
      { name = "windows_x86_64_msvc", version = "<0.52" },
      { name = "winnow", version = "0.5.40" },
+     { name = "x509-parser", version = "<0.16.0" },
 ]
 
 

src/config.rs

@@ -9,7 +9,7 @@ use base64::Engine as _;
 use deltachat_contact_tools::addr_cmp;
 use serde::{Deserialize, Serialize};
 use strum::{EnumProperty, IntoEnumIterator};
-use strum_macros::{AsRefStr, Display, EnumIter, EnumProperty, EnumString};
+use strum_macros::{AsRefStr, Display, EnumIter, EnumString};
 use tokio::fs;
 
 use crate::blob::BlobObject;
@@ -362,6 +362,9 @@ pub enum Config {
 
     /// MsgId of webxdc map integration.
     WebxdcIntegration,
+
+    /// Iroh secret key.
+    IrohSecretKey,
 }
 
 impl Config {

src/context.rs

@@ -12,7 +12,7 @@ use anyhow::{bail, ensure, Context as _, Result};
 use async_channel::{self as channel, Receiver, Sender};
 use pgp::SignedPublicKey;
 use ratelimit::Ratelimit;
-use tokio::sync::{Mutex, Notify, RwLock};
+use tokio::sync::{Mutex, Notify, OnceCell, RwLock};
 
 use crate::aheader::EncryptPreference;
 use crate::chat::{get_chat_cnt, ChatId, ProtectionStatus};
@@ -30,6 +30,7 @@ use crate::key::{load_self_public_key, load_self_secret_key, DcKey as _};
 use crate::login_param::LoginParam;
 use crate::message::{self, Message, MessageState, MsgId, Viewtype};
 use crate::param::{Param, Params};
+use crate::peer_channels::Iroh;
 use crate::peerstate::Peerstate;
 use crate::push::PushSubscriber;
 use crate::quota::QuotaInfo;
@@ -288,6 +289,9 @@ pub struct InnerContext {
 
     /// True if account has subscribed to push notifications via IMAP.
     pub(crate) push_subscribed: AtomicBool,
+
+    /// Iroh for realtime peer channels.
+    pub(crate) iroh: OnceCell<Iroh>,
 }
 
 /// The state of ongoing process.
@@ -445,6 +449,7 @@ impl Context {
             debug_logging: std::sync::RwLock::new(None),
             push_subscriber,
             push_subscribed: AtomicBool::new(false),
+            iroh: OnceCell::new(),
         };
 
         let ctx = Context {
@@ -482,6 +487,9 @@ impl Context {
 
     /// Indicate that the network likely has come back.
     pub async fn maybe_network(&self) {
+        if let Some(iroh) = self.iroh.get() {
+            iroh.network_change().await;
+        }
         self.scheduler.maybe_network().await;
     }
 
@@ -1648,6 +1656,7 @@ mod tests {
             "socks5_password",
             "key_id",
             "webxdc_integration",
+            "iroh_secret_key",
         ];
         let t = TestContext::new().await;
         let info = t.get_info().await.unwrap();

src/events/payload.rs

@@ -279,6 +279,15 @@ pub enum EventType {
         status_update_serial: StatusUpdateSerial,
     },
 
+    /// Data received over an ephemeral peer channel.
+    WebxdcRealtimeData {
+        /// Message ID.
+        msg_id: MsgId,
+
+        /// Realtime data.
+        data: Vec<u8>,
+    },
+
     /// Inform that a message containing a webxdc instance has been deleted.
     WebxdcInstanceDeleted {
         /// ID of the deleted message.

src/headerdef.rs

@@ -93,6 +93,12 @@ pub enum HeaderDef {
     /// See <https://datatracker.ietf.org/doc/html/rfc8601>
     AuthenticationResults,
 
+    /// Node address from iroh where direct addresses have been removed.
+    IrohNodeAddr,
+
+    /// Advertised gossip topic for one webxdc.
+    IrohGossipTopic,
+
     #[cfg(test)]
     TestHeader,
 }

src/imap.rs

@@ -22,6 +22,7 @@ use futures_lite::FutureExt;
 use num_traits::FromPrimitive;
 use rand::Rng;
 use ratelimit::Ratelimit;
+use url::Url;
 
 use crate::chat::{self, ChatId, ChatIdBlocked};
 use crate::chatlist_events;
@@ -111,6 +112,8 @@ pub(crate) struct ServerMetadata {
     /// IMAP METADATA `/shared/admin` as defined in
     /// <https://www.rfc-editor.org/rfc/rfc5464#section-6.2.2>.
     pub admin: Option<String>,
+
+    pub iroh_relay: Option<Url>,
 }
 
 impl async_imap::Authenticator for OAuth2 {
@@ -1449,11 +1452,16 @@ impl Session {
 
         let mut comment = None;
         let mut admin = None;
+        let mut iroh_relay = None;
 
         let mailbox = "";
         let options = "";
         let metadata = self
-            .get_metadata(mailbox, options, "(/shared/comment /shared/admin)")
+            .get_metadata(
+                mailbox,
+                options,
+                "(/shared/comment /shared/admin /shared/vendor/deltachat/irohrelay)",
+            )
             .await?;
         for m in metadata {
             match m.entry.as_ref() {
@@ -1463,10 +1471,24 @@ impl Session {
                 "/shared/admin" => {
                     admin = m.value;
                 }
+                "/shared/vendor/deltachat/irohrelay" => {
+                    if let Some(url) = m.value.as_deref().and_then(|s| Url::parse(s).ok()) {
+                        iroh_relay = Some(url);
+                    } else {
+                        warn!(
+                            context,
+                            "Got invalid URL from iroh relay metadata: {:?}.", m.value
+                        );
+                    }
+                }
                 _ => {}
             }
         }
-        *lock = Some(ServerMetadata { comment, admin });
+        *lock = Some(ServerMetadata {
+            comment,
+            admin,
+            iroh_relay,
+        });
         Ok(())
     }
 

src/imex/transfer.rs

@@ -38,6 +38,7 @@ use iroh::progress::ProgressEmitter;
 use iroh::protocol::AuthToken;
 use iroh::provider::{DataSource, Event, Provider, Ticket};
 use iroh::Hash;
+use iroh_old as iroh;
 use tokio::fs::{self, File};
 use tokio::io::{self, AsyncWriteExt, BufWriter};
 use tokio::sync::broadcast::error::RecvError;

src/lib.rs

@@ -106,6 +106,7 @@ pub mod receive_imf;
 pub mod tools;
 
 pub mod accounts;
+pub mod peer_channels;
 pub mod reaction;
 
 /// If set IMAP/incoming and SMTP/outgoing MIME messages will be printed.

src/mimefactory.rs

@@ -17,11 +17,12 @@ use crate::contact::Contact;
 use crate::context::Context;
 use crate::e2ee::EncryptHelper;
 use crate::ephemeral::Timer as EphemeralTimer;
+use crate::headerdef::HeaderDef;
 use crate::html::new_html_mimepart;
-use crate::location;
 use crate::message::{self, Message, MsgId, Viewtype};
 use crate::mimeparser::SystemMessage;
 use crate::param::Param;
+use crate::peer_channels::create_iroh_header;
 use crate::peerstate::Peerstate;
 use crate::simplify::escape_message_footer_marks;
 use crate::stock_str;
@@ -29,6 +30,7 @@ use crate::tools::IsNoneOrEmpty;
 use crate::tools::{
     create_outgoing_rfc724_mid, create_smeared_timestamp, remove_subject_prefix, time,
 };
+use crate::{location, peer_channels};
 
 // attachments of 25 mb brutto should work on the majority of providers
 // (brutto examples: web.de=50, 1&1=40, t-online.de=32, gmail=25, posteo=50, yahoo=25, all-inkl=100).
@@ -1148,6 +1150,18 @@ impl<'a> MimeFactory<'a> {
                     "protection-disabled".to_string(),
                 ));
             }
+            SystemMessage::IrohNodeAddr => {
+                headers.protected.push(Header::new(
+                    HeaderDef::IrohNodeAddr.get_headername().to_string(),
+                    serde_json::to_string(
+                        &context
+                            .get_or_try_init_peer_channel()
+                            .await?
+                            .get_node_addr()
+                            .await?,
+                    )?,
+                ));
+            }
             _ => {}
         }
 
@@ -1314,6 +1328,10 @@ impl<'a> MimeFactory<'a> {
             let json = self.msg.param.get(Param::Arg).unwrap_or_default();
             parts.push(context.build_status_update_part(json));
         } else if self.msg.viewtype == Viewtype::Webxdc {
+            let topic = peer_channels::create_random_topic();
+            headers
+                .protected
+                .push(create_iroh_header(context, topic, self.msg.id).await?);
             if let Some(json) = context
                 .render_webxdc_status_update_object(self.msg.id, None)
                 .await?

src/mimeparser.rs

@@ -199,6 +199,9 @@ pub enum SystemMessage {
 
     /// Webxdc info added with `info` set in `send_webxdc_status_update()`.
     WebxdcInfoMessage = 32,
+
+    /// This message contains a users iroh node address.
+    IrohNodeAddr = 40,
 }
 
 const MIME_AC_SETUP_FILE: &str = "application/autocrypt-setup";

src/peer_channels.rs

@@ -0,0 +1,711 @@
+//! Peer channels for realtime communication in webxdcs.
+//!
+//! We use Iroh as an ephemeral peer channels provider to create direct communication
+//! channels between webxdcs. See [here](https://webxdc.org/docs/spec/joinRealtimeChannel.html) for the webxdc specs.
+//!
+//! Ephemeral channels should be established lazily, to avoid bootstrapping p2p connectivity
+//! when it's not required. Only when a webxdc subscribes to realtime data or when a reatlime message is sent,
+//! the p2p machinery should be started.
+//!
+//! Adding peer channels to webxdc needs upfront negotation of a topic and sharing of public keys so that
+//! nodes can connect to each other. The explicit approach is as follows:
+//!
+//! 1. We introduce a new [GossipTopic](crate::headerdef::HeaderDef::IrohGossipTopic) message header with a random 32-byte TopicId,
+//!    securely generated on the initial webxdc sender's device. This message header is encrypted
+//!    and sent in the same message as the webxdc application.
+//! 2. Whenever `joinRealtimeChannel().setListener()` or `joinRealtimeChannel().send()` is called by the webxdc application,
+//!    we start a routine to establish p2p connectivity and join the gossip swarm with Iroh.
+//! 3. The first step of this routine is to introduce yourself with a regular message containing the `IrohPublicKey`.
+//!    This message contains the users relay-server and public key.
+//!    Direct IP address is not included as this information can be persisted by email providers.
+//! 4. After the announcement, the sending peer joins the gossip swarm with an empty list of peer IDs (as they don't know anyone yet).
+//! 5. Upon receiving an announcement message, other peers store the sender's [NodeAddr] in the database
+//!    (scoped per WebXDC app instance/message-id). The other peers can then join the gossip with `joinRealtimeChannel().setListener()`
+//!    and `joinRealtimeChannel().send()` just like the other peers.
+
+use anyhow::{anyhow, Context as _, Result};
+use email::Header;
+use iroh_gossip::net::{Gossip, JoinTopicFut, GOSSIP_ALPN};
+use iroh_gossip::proto::{Event as IrohEvent, TopicId};
+use iroh_net::relay::{RelayMap, RelayUrl};
+use iroh_net::{key::SecretKey, relay::RelayMode, MagicEndpoint};
+use iroh_net::{NodeAddr, NodeId};
+use std::collections::{BTreeSet, HashMap};
+use std::env;
+use tokio::sync::RwLock;
+use tokio::task::JoinHandle;
+use url::Url;
+
+use crate::chat::send_msg;
+use crate::context::Context;
+use crate::headerdef::HeaderDef;
+use crate::message::{Message, MsgId, Viewtype};
+use crate::mimeparser::SystemMessage;
+use crate::EventType;
+
+/// The length of an ed25519 `PublicKey`, in bytes.
+const PUBLIC_KEY_LENGTH: usize = 32;
+const PUBLIC_KEY_STUB: &[u8] = "static_string".as_bytes();
+
+/// Store iroh peer channels for the context.
+#[derive(Debug)]
+pub struct Iroh {
+    /// [MagicEndpoint] needed for iroh peer channels.
+    pub(crate) endpoint: MagicEndpoint,
+
+    /// [Gossip] needed for iroh peer channels.
+    pub(crate) gossip: Gossip,
+
+    /// Topics for which an advertisement has already been sent.
+    pub(crate) iroh_channels: RwLock<HashMap<TopicId, ChannelState>>,
+
+    /// Currently used Iroh secret key
+    pub(crate) secret_key: SecretKey,
+}
+
+impl Iroh {
+    /// Notify the endpoint that the network has changed.
+    pub(crate) async fn network_change(&self) {
+        self.endpoint.network_change().await
+    }
+
+    /// Join a topic and create the subscriber loop for it.
+    ///
+    /// If there is no gossip, create it.
+    ///
+    /// The returned future resolves when the swarm becomes operational.
+    async fn join_and_subscribe_gossip(
+        &self,
+        ctx: &Context,
+        msg_id: MsgId,
+    ) -> Result<Option<JoinTopicFut>> {
+        let topic = get_iroh_topic_for_msg(ctx, msg_id).await?;
+        let seq = if let Some(channel_state) = self.iroh_channels.read().await.get(&topic) {
+            if channel_state.subscribe_loop.is_some() {
+                return Ok(None);
+            }
+            channel_state.seq_number
+        } else {
+            0
+        };
+
+        let peers = get_iroh_gossip_peers(ctx, msg_id).await?;
+        info!(
+            ctx,
+            "IROH_REALTIME: Joining gossip with peers: {:?}",
+            peers.iter().map(|p| p.node_id).collect::<Vec<_>>()
+        );
+
+        // Connect to all peers
+        for peer in &peers {
+            self.endpoint.add_node_addr(peer.clone())?;
+        }
+
+        let connect_future = self
+            .gossip
+            .join(topic, peers.into_iter().map(|addr| addr.node_id).collect())
+            .await?;
+
+        let ctx = ctx.clone();
+        let gossip = self.gossip.clone();
+        let subscribe_loop = tokio::spawn(async move {
+            if let Err(e) = subscribe_loop(&ctx, gossip, topic, msg_id).await {
+                warn!(ctx, "subscribe_loop failed: {e}")
+            }
+        });
+
+        self.iroh_channels
+            .write()
+            .await
+            .insert(topic, ChannelState::new(seq, subscribe_loop));
+
+        Ok(Some(connect_future))
+    }
+
+    /// Send realtime data to the gossip swarm.
+    pub async fn send_webxdc_realtime_data(
+        &self,
+        ctx: &Context,
+        msg_id: MsgId,
+        mut data: Vec<u8>,
+    ) -> Result<()> {
+        let topic = get_iroh_topic_for_msg(ctx, msg_id).await?;
+        self.join_and_subscribe_gossip(ctx, msg_id).await?;
+
+        let seq_num = self.get_and_incr(&topic).await;
+        data.extend(seq_num.to_le_bytes());
+        data.extend(self.secret_key.public().as_bytes());
+
+        self.gossip.broadcast(topic, data.into()).await?;
+
+        if env::var("REALTIME_DEBUG").is_ok() {
+            info!(ctx, "Sent realtime data");
+        }
+
+        Ok(())
+    }
+
+    async fn get_and_incr(&self, topic: &TopicId) -> i32 {
+        let mut seq = 0;
+        if let Some(state) = self.iroh_channels.write().await.get_mut(topic) {
+            seq = state.seq_number;
+            state.seq_number = state.seq_number.wrapping_add(1)
+        }
+        seq
+    }
+
+    /// Get the iroh [NodeAddr] without direct IP addresses.
+    pub(crate) async fn get_node_addr(&self) -> Result<NodeAddr> {
+        let mut addr = self.endpoint.my_addr().await?;
+        addr.info.direct_addresses = BTreeSet::new();
+        Ok(addr)
+    }
+
+    /// Leave the realtime channel for a given topic.
+    pub(crate) async fn leave_realtime(&self, topic: TopicId) -> Result<()> {
+        if let Some(channel) = &mut self.iroh_channels.write().await.get_mut(&topic) {
+            if let Some(subscribe_loop) = channel.subscribe_loop.take() {
+                subscribe_loop.abort();
+            }
+        }
+        self.gossip.quit(topic).await?;
+        Ok(())
+    }
+}
+
+/// Single gossip channel state.
+#[derive(Debug)]
+pub(crate) struct ChannelState {
+    /// Sequence number for the gossip channel.
+    seq_number: i32,
+    /// The subscribe loop handle.
+    subscribe_loop: Option<JoinHandle<()>>,
+}
+
+impl ChannelState {
+    fn new(seq_number: i32, subscribe_loop: JoinHandle<()>) -> Self {
+        Self {
+            seq_number,
+            subscribe_loop: Some(subscribe_loop),
+        }
+    }
+}
+
+impl Context {
+    /// Create magic endpoint and gossip.
+    async fn init_peer_channels(&self) -> Result<Iroh> {
+        let secret_key: SecretKey = SecretKey::generate();
+
+        let relay_mode = if let Some(relay_url) = self
+            .metadata
+            .read()
+            .await
+            .as_ref()
+            .and_then(|conf| conf.iroh_relay.clone())
+        {
+            RelayMode::Custom(RelayMap::from_url(RelayUrl::from(relay_url)))
+        } else {
+            // FIXME: this should be RelayMode::Disabled instead.
+            // Currently using default relays because otherwise Rust tests fail.
+            RelayMode::Default
+        };
+
+        let endpoint = MagicEndpoint::builder()
+            .secret_key(secret_key.clone())
+            .alpns(vec![GOSSIP_ALPN.to_vec()])
+            .relay_mode(relay_mode)
+            .bind(0)
+            .await?;
+
+        // create gossip
+        let my_addr = endpoint.my_addr().await?;
+        let gossip = Gossip::from_endpoint(endpoint.clone(), Default::default(), &my_addr.info);
+
+        // spawn endpoint loop that forwards incoming connections to the gossiper
+        let context = self.clone();
+
+        // Shuts down on deltachat shutdown
+        tokio::spawn(endpoint_loop(context, endpoint.clone(), gossip.clone()));
+
+        Ok(Iroh {
+            endpoint,
+            gossip,
+            iroh_channels: RwLock::new(HashMap::new()),
+            secret_key,
+        })
+    }
+
+    /// Get or initialize the iroh peer channel.
+    pub async fn get_or_try_init_peer_channel(&self) -> Result<&Iroh> {
+        let ctx = self.clone();
+        self.iroh
+            .get_or_try_init(|| async { ctx.init_peer_channels().await })
+            .await
+    }
+}
+
+/// Cache a peers [NodeId] for one topic.
+pub(crate) async fn iroh_add_peer_for_topic(
+    ctx: &Context,
+    msg_id: MsgId,
+    topic: TopicId,
+    peer: NodeId,
+    relay_server: Option<&str>,
+) -> Result<()> {
+    ctx.sql
+        .execute(
+            "INSERT OR REPLACE INTO iroh_gossip_peers (msg_id, public_key, topic, relay_server) VALUES (?, ?, ?, ?)",
+            (msg_id, peer.as_bytes(), topic.as_bytes(), relay_server),
+        )
+        .await?;
+    Ok(())
+}
+
+/// Insert topicId into the database so that we can use it to retrieve the topic.
+pub(crate) async fn insert_topic_stub(ctx: &Context, msg_id: MsgId, topic: TopicId) -> Result<()> {
+    ctx.sql
+        .execute(
+            "INSERT OR REPLACE INTO iroh_gossip_peers (msg_id, public_key, topic, relay_server) VALUES (?, ?, ?, ?)",
+            (msg_id, PUBLIC_KEY_STUB, topic.as_bytes(), Option::<&str>::None),
+        )
+        .await?;
+    Ok(())
+}
+
+/// Get a list of [NodeAddr]s for one webxdc.
+async fn get_iroh_gossip_peers(ctx: &Context, msg_id: MsgId) -> Result<Vec<NodeAddr>> {
+    ctx.sql
+        .query_map(
+            "SELECT public_key, relay_server FROM iroh_gossip_peers WHERE msg_id = ? AND public_key != ?",
+            (msg_id, PUBLIC_KEY_STUB),
+            |row| {
+                let key:  Vec<u8> = row.get(0)?;
+                let server: Option<String> = row.get(1)?;
+                Ok((key, server))
+            },
+            |g| {
+                g.map(|data| {
+                    let (key, server) = data?;
+                    let server = server.map(|data| Ok::<_, url::ParseError>(RelayUrl::from(Url::parse(&data)?))).transpose()?;
+                    let id = NodeId::from_bytes(&key.try_into()
+                    .map_err(|_| anyhow!("Can't convert sql data to [u8; 32]"))?)?;
+                    Ok::<_, anyhow::Error>(NodeAddr::from_parts(
+                        id, server, vec![]
+                    ))
+                })
+                .collect::<std::result::Result<Vec<_>, _>>()
+                .map_err(Into::into)
+            },
+        )
+        .await
+}
+
+/// Get the topic for a given [MsgId].
+pub(crate) async fn get_iroh_topic_for_msg(ctx: &Context, msg_id: MsgId) -> Result<TopicId> {
+    let bytes: Vec<u8> = ctx
+        .sql
+        .query_get_value(
+            "SELECT topic FROM iroh_gossip_peers WHERE msg_id = ? LIMIT 1",
+            (msg_id,),
+        )
+        .await?
+        .context("couldn't restore topic from db")?;
+    Ok(TopicId::from_bytes(bytes.try_into().unwrap()))
+}
+
+/// Send a gossip advertisement to the chat that [MsgId] belongs to.
+/// This method should be called from the frontend when `joinRealtimeChannel` is called.
+pub async fn send_webxdc_realtime_advertisement(
+    ctx: &Context,
+    msg_id: MsgId,
+) -> Result<Option<JoinTopicFut>> {
+    let iroh = ctx.get_or_try_init_peer_channel().await?;
+    let conn = iroh.join_and_subscribe_gossip(ctx, msg_id).await?;
+
+    let webxdc = Message::load_from_db(ctx, msg_id).await?;
+    let mut msg = Message::new(Viewtype::Text);
+    msg.hidden = true;
+    msg.param.set_cmd(SystemMessage::IrohNodeAddr);
+    msg.in_reply_to = Some(webxdc.rfc724_mid.clone());
+    send_msg(ctx, webxdc.chat_id, &mut msg).await?;
+    info!(ctx, "IROH_REALTIME: Sent realtime advertisement");
+    Ok(conn)
+}
+
+/// Send realtime data to the gossip swarm.
+pub async fn send_webxdc_realtime_data(ctx: &Context, msg_id: MsgId, data: Vec<u8>) -> Result<()> {
+    let iroh = ctx.get_or_try_init_peer_channel().await?;
+    iroh.send_webxdc_realtime_data(ctx, msg_id, data).await?;
+    Ok(())
+}
+
+/// Leave the gossip of the webxdc with given [MsgId].
+pub async fn leave_webxdc_realtime(ctx: &Context, msg_id: MsgId) -> Result<()> {
+    let iroh = ctx.get_or_try_init_peer_channel().await?;
+    iroh.leave_realtime(get_iroh_topic_for_msg(ctx, msg_id).await?)
+        .await?;
+    info!(ctx, "IROH_REALTIME: Left gossip for message {msg_id}");
+
+    Ok(())
+}
+
+pub(crate) fn create_random_topic() -> TopicId {
+    TopicId::from_bytes(rand::random())
+}
+
+pub(crate) async fn create_iroh_header(
+    ctx: &Context,
+    topic: TopicId,
+    msg_id: MsgId,
+) -> Result<Header> {
+    insert_topic_stub(ctx, msg_id, topic).await?;
+    Ok(Header::new(
+        HeaderDef::IrohGossipTopic.get_headername().to_string(),
+        topic.to_string(),
+    ))
+}
+
+async fn endpoint_loop(context: Context, endpoint: MagicEndpoint, gossip: Gossip) {
+    while let Some(conn) = endpoint.accept().await {
+        info!(context, "IROH_REALTIME: accepting iroh connection");
+        let gossip = gossip.clone();
+        let context = context.clone();
+        tokio::spawn(async move {
+            if let Err(err) = handle_connection(&context, conn, gossip).await {
+                warn!(context, "IROH_REALTIME: iroh connection error: {err}");
+            }
+        });
+    }
+}
+
+async fn handle_connection(
+    context: &Context,
+    mut conn: iroh_net::magic_endpoint::Connecting,
+    gossip: Gossip,
+) -> anyhow::Result<()> {
+    let alpn = conn.alpn().await?;
+    let conn = conn.await?;
+    let peer_id = iroh_net::magic_endpoint::get_remote_node_id(&conn)?;
+
+    match alpn.as_bytes() {
+        GOSSIP_ALPN => gossip
+            .handle_connection(conn)
+            .await
+            .context(format!("Connection to {peer_id} with ALPN {alpn} failed"))?,
+        _ => warn!(
+            context,
+            "Ignoring connection from {peer_id}: unsupported ALPN protocol"
+        ),
+    }
+    Ok(())
+}
+
+async fn subscribe_loop(
+    context: &Context,
+    gossip: Gossip,
+    topic: TopicId,
+    msg_id: MsgId,
+) -> Result<()> {
+    let mut stream = gossip.subscribe(topic).await?;
+    loop {
+        let event = stream.recv().await?;
+        match event {
+            IrohEvent::NeighborUp(node) => {
+                info!(context, "IROH_REALTIME: NeighborUp: {}", node.to_string());
+                iroh_add_peer_for_topic(context, msg_id, topic, node, None).await?;
+            }
+            IrohEvent::Received(event) => {
+                info!(context, "IROH_REALTIME: Received realtime data");
+                context.emit_event(EventType::WebxdcRealtimeData {
+                    msg_id,
+                    data: event
+                        .content
+                        .get(0..event.content.len() - 4 - PUBLIC_KEY_LENGTH)
+                        .context("too few bytes in iroh message")?
+                        .into(),
+                });
+            }
+            _ => (),
+        };
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use crate::{
+        chat::send_msg,
+        message::{Message, Viewtype},
+        peer_channels::{
+            get_iroh_gossip_peers, get_iroh_topic_for_msg, leave_webxdc_realtime,
+            send_webxdc_realtime_advertisement,
+        },
+        test_utils::TestContextManager,
+        EventType,
+    };
+
+    #[tokio::test(flavor = "multi_thread", worker_threads = 2)]
+    async fn test_can_communicate() {
+        let mut tcm = TestContextManager::new();
+        let alice = &mut tcm.alice().await;
+        let bob = &mut tcm.bob().await;
+
+        // Alice sends webxdc to bob
+        let alice_chat = alice.create_chat(bob).await;
+        let mut instance = Message::new(Viewtype::File);
+        instance
+            .set_file_from_bytes(
+                alice,
+                "minimal.xdc",
+                include_bytes!("../test-data/webxdc/minimal.xdc"),
+                None,
+            )
+            .await
+            .unwrap();
+
+        send_msg(alice, alice_chat.id, &mut instance).await.unwrap();
+        let alice_webxdc = alice.get_last_msg().await;
+        assert_eq!(alice_webxdc.get_viewtype(), Viewtype::Webxdc);
+
+        let webxdc = alice.pop_sent_msg().await;
+        let bob_webdxc = bob.recv_msg(&webxdc).await;
+        assert_eq!(bob_webdxc.get_viewtype(), Viewtype::Webxdc);
+
+        bob_webdxc.chat_id.accept(bob).await.unwrap();
+
+        // Alice advertises herself.
+        send_webxdc_realtime_advertisement(alice, alice_webxdc.id)
+            .await
+            .unwrap();
+
+        bob.recv_msg_trash(&alice.pop_sent_msg().await).await;
+        let bob_iroh = bob.get_or_try_init_peer_channel().await.unwrap();
+
+        // Bob adds alice to gossip peers.
+        let members = get_iroh_gossip_peers(bob, bob_webdxc.id)
+            .await
+            .unwrap()
+            .into_iter()
+            .map(|addr| addr.node_id)
+            .collect::<Vec<_>>();
+
+        let alice_iroh = alice.get_or_try_init_peer_channel().await.unwrap();
+        assert_eq!(
+            members,
+            vec![alice_iroh.get_node_addr().await.unwrap().node_id]
+        );
+
+        bob_iroh
+            .join_and_subscribe_gossip(bob, bob_webdxc.id)
+            .await
+            .unwrap()
+            .unwrap()
+            .await
+            .unwrap();
+
+        // Alice sends ephemeral message
+        alice_iroh
+            .send_webxdc_realtime_data(alice, alice_webxdc.id, "alice -> bob".as_bytes().to_vec())
+            .await
+            .unwrap();
+
+        loop {
+            let event = bob.evtracker.recv().await.unwrap();
+            if let EventType::WebxdcRealtimeData { data, .. } = event.typ {
+                if data == "alice -> bob".as_bytes() {
+                    break;
+                } else {
+                    panic!(
+                        "Unexpected status update: {}",
+                        String::from_utf8_lossy(&data)
+                    );
+                }
+            }
+        }
+        // Bob sends ephemeral message
+        bob_iroh
+            .send_webxdc_realtime_data(bob, bob_webdxc.id, "bob -> alice".as_bytes().to_vec())
+            .await
+            .unwrap();
+
+        loop {
+            let event = alice.evtracker.recv().await.unwrap();
+            if let EventType::WebxdcRealtimeData { data, .. } = event.typ {
+                if data == "bob -> alice".as_bytes() {
+                    break;
+                } else {
+                    panic!(
+                        "Unexpected status update: {}",
+                        String::from_utf8_lossy(&data)
+                    );
+                }
+            }
+        }
+
+        // Alice adds bob to gossip peers.
+        let members = get_iroh_gossip_peers(alice, alice_webxdc.id)
+            .await
+            .unwrap()
+            .into_iter()
+            .map(|addr| addr.node_id)
+            .collect::<Vec<_>>();
+
+        assert_eq!(
+            members,
+            vec![bob_iroh.get_node_addr().await.unwrap().node_id]
+        );
+
+        bob_iroh
+            .send_webxdc_realtime_data(bob, bob_webdxc.id, "bob -> alice 2".as_bytes().to_vec())
+            .await
+            .unwrap();
+
+        loop {
+            let event = alice.evtracker.recv().await.unwrap();
+            if let EventType::WebxdcRealtimeData { data, .. } = event.typ {
+                if data == "bob -> alice 2".as_bytes() {
+                    break;
+                } else {
+                    panic!(
+                        "Unexpected status update: {}",
+                        String::from_utf8_lossy(&data)
+                    );
+                }
+            }
+        }
+    }
+
+    #[tokio::test(flavor = "multi_thread", worker_threads = 2)]
+    async fn test_can_reconnect() {
+        let mut tcm = TestContextManager::new();
+        let alice = &mut tcm.alice().await;
+        let bob = &mut tcm.bob().await;
+
+        // Alice sends webxdc to bob
+        let alice_chat = alice.create_chat(bob).await;
+        let mut instance = Message::new(Viewtype::File);
+        instance
+            .set_file_from_bytes(
+                alice,
+                "minimal.xdc",
+                include_bytes!("../test-data/webxdc/minimal.xdc"),
+                None,
+            )
+            .await
+            .unwrap();
+
+        send_msg(alice, alice_chat.id, &mut instance).await.unwrap();
+        let alice_webxdc = alice.get_last_msg().await;
+        assert_eq!(alice_webxdc.get_viewtype(), Viewtype::Webxdc);
+
+        let webxdc = alice.pop_sent_msg().await;
+        let bob_webdxc = bob.recv_msg(&webxdc).await;
+        assert_eq!(bob_webdxc.get_viewtype(), Viewtype::Webxdc);
+
+        bob_webdxc.chat_id.accept(bob).await.unwrap();
+
+        // Alice advertises herself.
+        send_webxdc_realtime_advertisement(alice, alice_webxdc.id)
+            .await
+            .unwrap();
+
+        bob.recv_msg_trash(&alice.pop_sent_msg().await).await;
+        let bob_iroh = bob.get_or_try_init_peer_channel().await.unwrap();
+
+        // Bob adds alice to gossip peers.
+        let members = get_iroh_gossip_peers(bob, bob_webdxc.id)
+            .await
+            .unwrap()
+            .into_iter()
+            .map(|addr| addr.node_id)
+            .collect::<Vec<_>>();
+
+        let alice_iroh = alice.get_or_try_init_peer_channel().await.unwrap();
+        assert_eq!(
+            members,
+            vec![alice_iroh.get_node_addr().await.unwrap().node_id]
+        );
+
+        bob_iroh
+            .join_and_subscribe_gossip(bob, bob_webdxc.id)
+            .await
+            .unwrap()
+            .unwrap()
+            .await
+            .unwrap();
+
+        // Alice sends ephemeral message
+        alice_iroh
+            .send_webxdc_realtime_data(alice, alice_webxdc.id, "alice -> bob".as_bytes().to_vec())
+            .await
+            .unwrap();
+
+        loop {
+            let event = bob.evtracker.recv().await.unwrap();
+            if let EventType::WebxdcRealtimeData { data, .. } = event.typ {
+                if data == "alice -> bob".as_bytes() {
+                    break;
+                } else {
+                    panic!(
+                        "Unexpected status update: {}",
+                        String::from_utf8_lossy(&data)
+                    );
+                }
+            }
+        }
+
+        // TODO: check that seq number is persisted
+        leave_webxdc_realtime(bob, bob_webdxc.id).await.unwrap();
+
+        bob_iroh
+            .join_and_subscribe_gossip(bob, bob_webdxc.id)
+            .await
+            .unwrap()
+            .unwrap()
+            .await
+            .unwrap();
+
+        bob_iroh
+            .send_webxdc_realtime_data(bob, bob_webdxc.id, "bob -> alice".as_bytes().to_vec())
+            .await
+            .unwrap();
+
+        loop {
+            let event = alice.evtracker.recv().await.unwrap();
+            if let EventType::WebxdcRealtimeData { data, .. } = event.typ {
+                if data == "bob -> alice".as_bytes() {
+                    break;
+                } else {
+                    panic!(
+                        "Unexpected status update: {}",
+                        String::from_utf8_lossy(&data)
+                    );
+                }
+            }
+        }
+
+        // channel is only used to remeber if an advertisement has been sent
+        // bob for example does not change the channels because he never sends an
+        // advertisement
+        assert_eq!(
+            alice.iroh.get().unwrap().iroh_channels.read().await.len(),
+            1
+        );
+        leave_webxdc_realtime(alice, alice_webxdc.id).await.unwrap();
+        let topic = get_iroh_topic_for_msg(alice, alice_webxdc.id)
+            .await
+            .unwrap();
+        assert!(if let Some(state) = alice
+            .iroh
+            .get()
+            .unwrap()
+            .iroh_channels
+            .read()
+            .await
+            .get(&topic)
+        {
+            state.subscribe_loop.is_none()
+        } else {
+            false
+        });
+    }
+}

src/qr.rs

@@ -23,6 +23,7 @@ use crate::peerstate::Peerstate;
 use crate::socks::Socks5Config;
 use crate::token;
 use crate::tools::validate_id;
+use iroh_old as iroh;
 
 const OPENPGP4FPR_SCHEME: &str = "OPENPGP4FPR:"; // yes: uppercase
 const IDELTACHAT_SCHEME: &str = "https://i.delta.chat/#";

src/receive_imf.rs

@@ -1,11 +1,13 @@
 //! Internet Message Format reception pipeline.
 
 use std::collections::HashSet;
+use std::str::FromStr;
 
 use anyhow::{Context as _, Result};
 use deltachat_contact_tools::{
     addr_cmp, may_be_valid_addr, normalize_name, strip_rtlo_characters, ContactAddress,
 };
+use iroh_gossip::proto::TopicId;
 use mailparse::{parse_mail, SingleInfo};
 use num_traits::FromPrimitive;
 use once_cell::sync::Lazy;
@@ -30,6 +32,7 @@ use crate::message::{
 };
 use crate::mimeparser::{parse_message_ids, AvatarAction, MimeMessage, SystemMessage};
 use crate::param::{Param, Params};
+use crate::peer_channels::{get_iroh_topic_for_msg, insert_topic_stub, iroh_add_peer_for_topic};
 use crate::peerstate::Peerstate;
 use crate::reaction::{set_msg_reaction, Reaction};
 use crate::securejoin::{self, handle_securejoin_handshake, observe_securejoin_on_other_device};
@@ -40,6 +43,7 @@ use crate::sync::Sync::*;
 use crate::tools::{self, buf_compress, extract_grpid_from_rfc724_mid};
 use crate::{chatlist_events, location};
 use crate::{contact, imap};
+use iroh_net::NodeAddr;
 
 /// This is the struct that is returned after receiving one email (aka MIME message).
 ///
@@ -1220,7 +1224,7 @@ async fn add_parts(
     }
 
     let orig_chat_id = chat_id;
-    let chat_id = if is_mdn || is_reaction {
+    let mut chat_id = if is_mdn || is_reaction {
         DC_CHAT_ID_TRASH
     } else {
         chat_id.unwrap_or_else(|| {
@@ -1430,6 +1434,24 @@ async fn add_parts(
         .await?;
     }
 
+    if let Some(node_addr) = mime_parser.get_header(HeaderDef::IrohNodeAddr) {
+        match serde_json::from_str::<NodeAddr>(node_addr).context("Failed to parse node address") {
+            Ok(node_addr) => {
+                info!(context, "Adding iroh peer with address {node_addr:?}.");
+                let instance_id = parent.context("Failed to get parent message")?.id;
+                let node_id = node_addr.node_id;
+                let relay_server = node_addr.relay_url().map(|relay| relay.as_str());
+                let topic = get_iroh_topic_for_msg(context, instance_id).await?;
+                iroh_add_peer_for_topic(context, instance_id, topic, node_id, relay_server).await?;
+
+                chat_id = DC_CHAT_ID_TRASH;
+            }
+            Err(err) => {
+                warn!(context, "Couldn't parse NodeAddr: {err:#}.");
+            }
+        }
+    }
+
     for part in &mime_parser.parts {
         if part.is_reaction {
             let reaction_str = simplify::remove_footers(part.msg.as_str());
@@ -1597,6 +1619,16 @@ RETURNING id
 
     // check all parts whether they contain a new logging webxdc
     for (part, msg_id) in mime_parser.parts.iter().zip(&created_db_entries) {
+        // check if any part contains a webxdc topic id
+        if part.typ == Viewtype::Webxdc {
+            if let Some(topic) = mime_parser.get_header(HeaderDef::IrohGossipTopic) {
+                let topic = TopicId::from_str(topic).context("wrong gossip topic header")?;
+                insert_topic_stub(context, *msg_id, topic).await?;
+            } else {
+                warn!(context, "webxdc doesn't have a gossip topic")
+            }
+        }
+
         maybe_set_logging_xdc_inner(
             context,
             part.typ,

src/sql/migrations.rs

@@ -912,6 +912,30 @@ CREATE INDEX msgs_status_updates_index2 ON msgs_status_updates (uid);
         .await?;
     }
 
+    if dbversion < 111 {
+        sql.execute_migration(
+            "CREATE TABLE iroh_gossip_peers (msg_id TEXT not NULL, topic TEXT NOT NULL, public_key TEXT NOT NULL)",
+            111,
+        )
+        .await?;
+    }
+
+    if dbversion < 112 {
+        sql.execute_migration(
+            "DROP TABLE iroh_gossip_peers; CREATE TABLE iroh_gossip_peers (msg_id INTEGER not NULL, topic BLOB NOT NULL, public_key BLOB NOT NULL, relay_server TEXT, UNIQUE (public_key, topic)) STRICT",
+            112,
+        )
+        .await?;
+    }
+
+    if dbversion < 113 {
+        sql.execute_migration(
+            "DROP TABLE iroh_gossip_peers; CREATE TABLE iroh_gossip_peers (msg_id INTEGER not NULL, topic BLOB NOT NULL, public_key BLOB NOT NULL, relay_server TEXT, UNIQUE (topic, public_key), PRIMARY KEY(topic, public_key)) STRICT",
+            113,
+        )
+        .await?;
+    }
+
     let new_version = sql
         .get_raw_config_int(VERSION_CFG)
         .await?