Files
hbb_common/src/webrtc.rs
T
2026-08-22 13:21:01 +08:00

1298 lines
53 KiB
Rust

use std::collections::HashMap;
use std::io::{Error, ErrorKind};
use std::net::{IpAddr, Ipv4Addr, SocketAddr};
use std::sync::atomic::{AtomicBool, Ordering};
use std::sync::{Arc, Mutex as StdMutex};
use std::time::Duration;
use webrtc::api::setting_engine::SettingEngine;
use webrtc::api::APIBuilder;
use webrtc::data::data_channel::DataChannel as DetachedDataChannel;
use webrtc::data_channel::RTCDataChannel;
use webrtc::ice::mdns::MulticastDnsMode;
use webrtc::ice_transport::ice_candidate::RTCIceCandidateInit;
use webrtc::ice_transport::ice_candidate_type::RTCIceCandidateType;
use webrtc::ice_transport::ice_server::RTCIceServer;
use webrtc::peer_connection::configuration::RTCConfiguration;
use webrtc::peer_connection::peer_connection_state::RTCPeerConnectionState;
use webrtc::peer_connection::policy::ice_transport_policy::RTCIceTransportPolicy;
use webrtc::peer_connection::sdp::session_description::RTCSessionDescription;
use webrtc::peer_connection::RTCPeerConnection;
use webrtc::stats::StatsReportType;
use base64::engine::general_purpose::STANDARD as BASE64_STANDARD;
use base64::Engine;
use bytes::{BufMut, Bytes, BytesMut};
use tokio::sync::{mpsc, watch, Mutex, Semaphore};
use tokio::time::{timeout, timeout_at, Instant};
use url::Url;
use crate::bytes_codec::MAX_FRAME_LENGTH;
use crate::config;
use crate::protobuf::Message;
use crate::sodiumoxide::crypto::secretbox::Key;
use crate::ResultType;
#[derive(Clone, Debug, PartialEq, Eq)]
enum WebRTCConnectionState {
Pending,
Open,
Closed(String),
}
pub struct WebRTCStream {
pc: Arc<RTCPeerConnection>,
stream: Arc<Mutex<Arc<RTCDataChannel>>>,
state_notify: watch::Receiver<WebRTCConnectionState>,
local_ice_rx: Arc<StdMutex<Option<mpsc::UnboundedReceiver<String>>>>,
session_key: String,
send_timeout: u64,
// Built with Relay-only ICE policy (force_relay): every selected pair goes through TURN.
relay_only: bool,
// Detached data channel, cached after the first `detach()` so send/recv do not re-lock and
// re-fetch it per message. Shared across clones; `detach()` is idempotent.
detached: Arc<Mutex<Option<Arc<DetachedDataChannel>>>>,
// Serialize a complete logical message across clones. Each fragment is a separate SCTP
// message, so serializing only individual writes would allow two large messages to interleave.
send_gate: Arc<Semaphore>,
// Receive-side reassembly state, guarded by a single mutex so the fragment accumulator
// survives `next()` cancellation (e.g. `next_timeout`) instead of losing already-read
// fragments mid-message. Assumes a single reader, consistent with the rest of the stream API.
recv_state: Arc<Mutex<RecvState>>,
// True once the controller has completed the RustDesk identity binding (DTLS fingerprint
// matched to the signed peer id, via `set_key`). DTLS always encrypts; this flag mirrors TCP's
// "secured after key exchange" so key-less / unbound WebRTC is not shown as peer-authenticated.
peer_verified: Arc<AtomicBool>,
}
#[derive(Default)]
struct RecvState {
// Accumulated payload of the logical message currently being reassembled.
acc: BytesMut,
// Reused read scratch buffer, avoiding a per-message allocation.
scratch: Vec<u8>,
}
// The SCTP data channel's 65536-byte max message size is handled by
// splitting a logical message into fragments carrying a 1-byte header. Fragment payload is kept
// well under the limit so header+payload never reaches the exact-65536 boundary that the
// receiver's reassembly would truncate with data loss.
const MAX_FRAGMENT_PAYLOAD: usize = 60000;
/// Receive scratch size: must be >= 1 (fragment header) + `MAX_FRAGMENT_PAYLOAD` and fit the
/// negotiated SCTP max message size.
const RECV_BUF_SIZE: usize = 64 * 1024;
/// Fragment header byte: more fragments follow for this logical message.
const FRAG_MORE: u8 = 1;
/// Fragment header byte: final (or only) fragment of a logical message.
const FRAG_END: u8 = 0;
// use 3 public STUN servers to find out the NAT type, 2 must be the same address but different ports
// https://stackoverflow.com/questions/72805316/determine-nat-mapping-behaviour-using-two-stun-servers
// luckily nextcloud supports two ports for STUN
// unluckily webrtc-rs does not use the same port to do the STUN request
static DEFAULT_ICE_SERVERS: [&str; 3] = [
"stun:stun.cloudflare.com:3478",
"stun:stun.nextcloud.com:3478",
"stun:stun.nextcloud.com:443",
];
lazy_static::lazy_static! {
static ref SESSIONS: Arc::<Mutex<HashMap<String, WebRTCStream>>> = Default::default();
}
impl Clone for WebRTCStream {
fn clone(&self) -> Self {
WebRTCStream {
pc: self.pc.clone(),
stream: self.stream.clone(),
state_notify: self.state_notify.clone(),
local_ice_rx: self.local_ice_rx.clone(),
session_key: self.session_key.clone(),
send_timeout: self.send_timeout,
relay_only: self.relay_only,
detached: self.detached.clone(),
send_gate: self.send_gate.clone(),
recv_state: self.recv_state.clone(),
peer_verified: self.peer_verified.clone(),
}
}
}
impl WebRTCStream {
#[inline]
fn get_remote_offer(endpoint: &str) -> ResultType<String> {
// Ensure the endpoint starts with the "webrtc://" prefix
if !endpoint.starts_with("webrtc://") {
return Err(
Error::new(ErrorKind::InvalidInput, "Invalid WebRTC endpoint format").into(),
);
}
// Extract the Base64-encoded SDP part
let encoded_sdp = &endpoint["webrtc://".len()..];
// Decode the Base64 string
let decoded_bytes = BASE64_STANDARD
.decode(encoded_sdp)
.map_err(|_| Error::new(ErrorKind::InvalidInput, "Failed to decode Base64 SDP"))?;
Ok(String::from_utf8(decoded_bytes).map_err(|_| {
Error::new(
ErrorKind::InvalidInput,
"Failed to convert decoded bytes to UTF-8",
)
})?)
}
#[inline]
fn sdp_to_endpoint(sdp: &str) -> String {
let encoded_sdp = BASE64_STANDARD.encode(sdp);
format!("webrtc://{}", encoded_sdp)
}
#[inline]
fn get_key_for_sdp(sdp: &RTCSessionDescription) -> ResultType<String> {
let binding = sdp.unmarshal()?;
let Some(fingerprint) = binding.attribute("fingerprint") else {
// find fingerprint attribute in media descriptions
for media in &binding.media_descriptions {
if media.media_name.media != "application" {
continue;
}
if let Some(fp) = media
.attributes
.iter()
.find(|x| x.key == "fingerprint")
.and_then(|x| x.value.clone())
{
return Ok(fp);
}
}
return Err(anyhow::anyhow!("SDP fingerprint attribute not found"));
};
Ok(fingerprint.to_string())
}
/// Process-local SESSIONS-map key: the DTLS fingerprint prefixed by role. An offerer and an
/// answerer that share a fingerprint (a single process connecting to its own id) would
/// otherwise collide, handing the offerer back as the answerer. The wire-level `session_key`
/// used for ICE-candidate routing stays the bare fingerprint so both peers still match.
#[inline]
fn cache_key(fingerprint: &str, is_offerer: bool) -> String {
format!(
"{}:{}",
if is_offerer { "offer" } else { "answer" },
fingerprint
)
}
#[inline]
fn get_key_for_sdp_json(sdp_json: &str) -> ResultType<String> {
if sdp_json.is_empty() {
return Ok("".to_string());
}
let sdp = serde_json::from_str::<RTCSessionDescription>(sdp_json)?;
Self::get_key_for_sdp(&sdp)
}
#[inline]
async fn get_key_for_peer(pc: &Arc<RTCPeerConnection>, is_local: bool) -> ResultType<String> {
let Some(desc) = (match is_local {
true => pc.local_description().await,
false => pc.remote_description().await,
}) else {
return Err(anyhow::anyhow!("PeerConnection description is not set"));
};
Self::get_key_for_sdp(&desc)
}
#[inline]
fn get_ice_server_from_url(url: &str) -> Option<RTCIceServer> {
// standard url format with turn scheme: turn://user:pass@host:port
match Url::parse(url) {
Ok(u) => {
if u.scheme() == "turn"
|| u.scheme() == "turns"
|| u.scheme() == "stun"
|| u.scheme() == "stuns"
{
Some(RTCIceServer {
urls: vec![format!(
"{}:{}:{}",
u.scheme(),
u.host_str().unwrap_or_default(),
u.port().unwrap_or(3478)
)],
username: u.username().to_string(),
credential: u.password().unwrap_or_default().to_string(),
..Default::default()
})
} else {
None
}
}
Err(_) => None,
}
}
/// Whether the ICE configuration contains a usable TURN server. A Relay-policy peer
/// connection (force_relay) can only gather relay candidates, so without a TURN server it can
/// never connect — callers use this to skip building a guaranteed-dead pc.
pub fn has_turn_server() -> bool {
Self::get_ice_servers().iter().any(|s| {
s.urls
.iter()
.any(|u| u.starts_with("turn:") || u.starts_with("turns:"))
})
}
#[inline]
fn get_ice_servers() -> Vec<RTCIceServer> {
let mut ice_servers = Vec::new();
let cfg = config::Config::get_option(config::keys::OPTION_ICE_SERVERS);
let mut has_stun = false;
for url in cfg.split(',').map(str::trim) {
if let Some(ice_server) = Self::get_ice_server_from_url(url) {
// Detect STUN in user config
if ice_server
.urls
.iter()
.any(|u| u.starts_with("stun:") || u.starts_with("stuns:"))
{
has_stun = true;
}
ice_servers.push(ice_server);
}
}
// If there is no STUN (either TURN-only or empty config) → prepend defaults
if !has_stun {
ice_servers.insert(
0,
RTCIceServer {
urls: DEFAULT_ICE_SERVERS.iter().map(|s| s.to_string()).collect(),
..Default::default()
},
);
}
ice_servers
}
pub async fn new(
remote_endpoint: &str,
force_relay: bool,
ms_timeout: u64,
) -> ResultType<Self> {
// The endpoint contains a Base64-encoded SDP with host addresses and live ICE
// credentials. Log only its size so debug logs cannot disclose that information.
log::debug!(
"New webrtc stream (remote endpoint: {} bytes)",
remote_endpoint.len()
);
let remote_offer = if remote_endpoint.is_empty() {
"".into()
} else {
Self::get_remote_offer(remote_endpoint)?
};
let mut key = Self::get_key_for_sdp_json(&remote_offer)?;
let start_local_offer = remote_offer.is_empty();
if !key.is_empty() {
let sessions_lock = SESSIONS.lock().await;
if let Some(cached_stream) =
sessions_lock.get(&Self::cache_key(&key, start_local_offer))
{
log::debug!("Start webrtc with cached peer");
return Ok(cached_stream.clone());
}
}
// Create a SettingEngine and enable Detach
let mut s = SettingEngine::default();
s.detach_data_channels();
s.set_ice_multicast_dns_mode(MulticastDnsMode::Disabled);
// Create the API object
let api = APIBuilder::new().with_setting_engine(s).build();
// Prepare the configuration, get ICE servers from config
let config = RTCConfiguration {
ice_servers: Self::get_ice_servers(),
ice_transport_policy: if force_relay {
RTCIceTransportPolicy::Relay
} else {
RTCIceTransportPolicy::All
},
..Default::default()
};
let (notify_tx, notify_rx) = watch::channel(WebRTCConnectionState::Pending);
let (ice_tx, ice_rx) = mpsc::unbounded_channel::<String>();
// Create a new RTCPeerConnection
let pc = Arc::new(api.new_peer_connection(config).await?);
let local_ice_tx = ice_tx.clone();
pc.on_ice_candidate(Box::new(move |candidate| {
let local_ice_tx = local_ice_tx.clone();
Box::pin(async move {
let Some(candidate) = candidate else {
return;
};
match candidate.to_json() {
Ok(candidate) => match serde_json::to_string(&candidate) {
Ok(candidate_json) => {
let _ = local_ice_tx.send(candidate_json);
}
Err(err) => {
log::warn!("failed to serialize local ICE candidate: {}", err);
}
},
Err(err) => {
log::warn!("failed to convert local ICE candidate to JSON: {}", err);
}
}
})
}));
let bootstrap_dc = if start_local_offer {
let dc_open_notify = notify_tx.clone();
// Create a data channel with label "bootstrap"
let dc = match pc.create_data_channel("bootstrap", None).await {
Ok(dc) => dc,
Err(e) => {
// Close before propagating: the pc is live and would otherwise leak.
pc.close().await.ok();
return Err(e.into());
}
};
dc.on_open(Box::new(move || {
log::debug!("Local data channel bootstrap open.");
let _ = dc_open_notify.send(WebRTCConnectionState::Open);
Box::pin(async {})
}));
dc
} else {
// Wait for the data channel to be created by the remote peer
// Here we create a dummy data channel to satisfy the type system
Arc::new(RTCDataChannel::default())
};
let stream = Arc::new(Mutex::new(bootstrap_dc));
if !start_local_offer {
// Register data channel creation handling
let dc_open_notify = notify_tx.clone();
let stream_for_dc = stream.clone();
pc.on_data_channel(Box::new(move |dc: Arc<RTCDataChannel>| {
let d_label = dc.label().to_owned();
let dc_open_notify2 = dc_open_notify.clone();
let stream_for_dc_clone = stream_for_dc.clone();
log::debug!("Remote data channel {} ready", d_label);
Box::pin(async move {
let mut stream_lock = stream_for_dc_clone.lock().await;
*stream_lock = dc.clone();
drop(stream_lock);
dc.on_open(Box::new(move || {
let _ = dc_open_notify2.send(WebRTCConnectionState::Open);
Box::pin(async {})
}));
})
}));
}
// This will notify you when the peer has connected/disconnected
let stream_for_close = stream.clone();
// Weak, not strong: a handler stored inside the pc that captured a strong
// `Arc<RTCPeerConnection>` forms a pc -> internal -> handler -> pc cycle that `close()`
// never breaks (it only fires the handler) and no `Drop` clears, permanently leaking every
// pc and the ICE-candidate sender's forwarding task. Upgrade inside the handler; if the pc
// is already gone there is nothing left in SESSIONS to evict.
let pc_for_close = Arc::downgrade(&pc);
pc.on_peer_connection_state_change(Box::new(move |s: RTCPeerConnectionState| {
let stream_for_close2 = stream_for_close.clone();
let on_connection_notify = notify_tx.clone();
let pc_for_close2 = pc_for_close.clone();
Box::pin(async move {
log::debug!("WebRTC session peer connection state: {}", s);
match s {
// `Disconnected` is a transient, recoverable ICE state (webrtc-ice fires it
// after ~5s without consent and returns to `Connected` when traffic resumes).
// Only tear down on the terminal states so a short network blip (Wi-Fi roam,
// sleep/wake, cell handover) does not permanently kill an established session.
RTCPeerConnectionState::Failed | RTCPeerConnectionState::Closed => {
let _ = on_connection_notify.send(WebRTCConnectionState::Closed(
s.to_string(),
));
log::debug!("WebRTC session closing due to {}", s);
let _ = stream_for_close2.lock().await.close().await;
log::debug!("WebRTC session stream closed");
let Some(pc_for_close2) = pc_for_close2.upgrade() else {
return;
};
let mut sessions_lock = SESSIONS.lock().await;
match Self::get_key_for_peer(&pc_for_close2, start_local_offer).await {
Ok(fingerprint) => {
let k = Self::cache_key(&fingerprint, start_local_offer);
// Only evict if the cached entry IS this pc: a duplicate offer
// resolves to the same key, and closing the discarded duplicate pc
// must not remove the live winner sharing that key.
if sessions_lock
.get(&k)
.is_some_and(|s| Arc::ptr_eq(&s.pc, &pc_for_close2))
{
sessions_lock.remove(&k);
log::debug!("WebRTC session removed key: {}", k);
}
}
Err(e) => {
log::error!(
"Failed to extract key for peer during session cleanup: {:?}",
e
);
// Fallback: try to remove any session associated with this peer connection
let keys_to_remove: Vec<String> = sessions_lock
.iter()
.filter_map(|(key, session)| {
if Arc::ptr_eq(&session.pc, &pc_for_close2) {
Some(key.clone())
} else {
None
}
})
.collect();
for k in keys_to_remove {
sessions_lock.remove(&k);
log::debug!("WebRTC session removed by fallback key: {}", k);
}
}
}
}
_ => {}
}
})
}));
// process offer/answer
//
// Trickle ICE: the local description is returned WITHOUT waiting for candidate gathering
// (candidates stream out via `take_local_ice_rx` afterwards), so this block is local-only
// work — pc construction, DTLS cert keygen, SDP marshal — at sub-millisecond cost. The
// controlled side awaits answer creation inline on its punch-reply critical path and
// relies on that: adding any gathering/network wait here would delay the TCP/UDP
// hole-punch reply for every connection.
// Any failure below leaves a live pc with handlers already registered; its state handler
// only fires on a terminal ICE state, so a bare `?`-drop would leak it (remotely
// triggerable: a crafted `type:"answer"` offer passes the JSON+fingerprint pre-check but
// fails `set_remote_description`). Close the pc before propagating any such error.
let offer_answer: ResultType<String> = async {
if start_local_offer {
let sdp = pc.create_offer(None).await?;
pc.set_local_description(sdp.clone()).await?;
// SDP carries host/srflx IPs and ICE ufrag/pwd; log only its size, not the body.
log::debug!("local offer SDP built ({} bytes)", sdp.sdp.len());
let k = Self::get_key_for_sdp(&sdp)?;
log::debug!("Start webrtc with local key: {}", k);
Ok(k)
} else {
let sdp = serde_json::from_str::<RTCSessionDescription>(&remote_offer)?;
pc.set_remote_description(sdp.clone()).await?;
let answer = pc.create_answer(None).await?;
pc.set_local_description(answer).await?;
log::debug!("remote offer SDP received ({} bytes)", sdp.sdp.len());
let k = Self::get_key_for_sdp(&sdp)?;
log::debug!("Start webrtc with remote key: {}", k);
Ok(k)
}
}
.await;
key = match offer_answer {
Ok(k) => k,
Err(e) => {
pc.close().await.ok();
return Err(e);
}
};
let webrtc_stream = Self {
pc,
stream,
state_notify: notify_rx,
local_ice_rx: Arc::new(StdMutex::new(Some(ice_rx))),
session_key: key.clone(),
send_timeout: ms_timeout,
relay_only: force_relay,
detached: Arc::new(Mutex::new(None)),
send_gate: Arc::new(Semaphore::new(1)),
recv_state: Arc::new(Mutex::new(RecvState::default())),
peer_verified: Arc::new(AtomicBool::new(false)),
};
// Insert into the session cache, but never `await pc.close()` while holding this lock:
// `close()` fires the peer-connection-state handler inline, which itself locks SESSIONS,
// self-deadlocking the whole process. Resolve any duplicate off-lock.
let cache_key = Self::cache_key(&key, start_local_offer);
let duplicate = {
let mut final_lock = SESSIONS.lock().await;
if let Some(session) = final_lock.get(&cache_key) {
Some(session.clone())
} else {
final_lock.insert(cache_key, webrtc_stream.clone());
None
}
};
if let Some(session) = duplicate {
// A concurrent `new()` already cached an equivalent stream; discard this pc's
// resources (off-lock) and return the cached one.
webrtc_stream.close().await;
return Ok(session);
}
Ok(webrtc_stream)
}
#[inline]
pub async fn get_local_endpoint(&self) -> ResultType<String> {
// Preserve the original one-shot endpoint contract: callers that only exchange this SDP
// do not have a separate path for `take_local_ice_rx`, so their endpoint must contain the
// gathered host/srflx/relay candidates.
let mut gather_complete = self.pc.gathering_complete_promise().await;
let _gathering_channel_closed = gather_complete.recv().await;
self.get_local_endpoint_trickle().await
}
/// Return the current local description immediately for callers that signal candidates via
/// `take_local_ice_rx`. Unlike `get_local_endpoint`, this does not wait for ICE gathering.
#[inline]
pub async fn get_local_endpoint_trickle(&self) -> ResultType<String> {
if let Some(local_desc) = self.pc.local_description().await {
let sdp = serde_json::to_string(&local_desc)?;
let endpoint = Self::sdp_to_endpoint(&sdp);
Ok(endpoint)
} else {
Err(anyhow::anyhow!("Local desc is not set"))
}
}
#[inline]
pub async fn set_remote_endpoint(&self, endpoint: &str) -> ResultType<()> {
let offer = Self::get_remote_offer(endpoint)?;
log::debug!("WebRTC set remote sdp ({} bytes)", offer.len());
let sdp = serde_json::from_str::<RTCSessionDescription>(&offer)?;
self.pc.set_remote_description(sdp).await?;
Ok(())
}
/// DTLS certificate fingerprint of the local description (this endpoint's own cert).
#[inline]
pub async fn local_dtls_fingerprint(&self) -> ResultType<String> {
Self::get_key_for_peer(&self.pc, true).await
}
/// DTLS certificate fingerprint of the remote description (the peer's cert). webrtc-rs
/// verifies the negotiated peer certificate against this fingerprint during the DTLS
/// handshake, so once the channel is open a matching fingerprint identifies the peer's cert.
#[inline]
pub async fn remote_dtls_fingerprint(&self) -> ResultType<String> {
Self::get_key_for_peer(&self.pc, false).await
}
/// Whether the established connection runs through a TURN relay: `Some(true)` when the pc is
/// Relay-policy (TURN is the only possibility) or the selected ICE candidate pair uses a
/// relay candidate; `None` before a pair is selected. Feeds the UI's direct/relayed flag.
pub async fn is_relayed(&self) -> Option<bool> {
if self.relay_only {
return Some(true);
}
let dtls = self.pc.sctp().transport();
dtls.ice_transport().get_selected_candidate_pair().await?;
// webrtc 0.13 keeps RTCIceCandidatePair's candidates private. Its stats report exposes
// the selected (nominated) pair and the corresponding candidate types instead.
let stats = self.pc.get_stats().await;
let pair = stats.reports.values().find_map(|report| match report {
StatsReportType::CandidatePair(pair) if pair.nominated => Some(pair),
_ => None,
})?;
let is_relay = |candidate_id: &str| {
matches!(
stats.reports.get(candidate_id),
Some(
StatsReportType::LocalCandidate(candidate)
| StatsReportType::RemoteCandidate(candidate)
) if RTCIceCandidateType::from(candidate.candidate_type)
== RTCIceCandidateType::Relay
)
};
Some(
is_relay(&pair.local_candidate_id) || is_relay(&pair.remote_candidate_id),
)
}
#[inline]
pub fn take_local_ice_rx(&self) -> Option<mpsc::UnboundedReceiver<String>> {
self.local_ice_rx.lock().ok().and_then(|mut rx| rx.take())
}
#[inline]
pub async fn add_remote_ice_candidate(&self, candidate_json: &str) -> ResultType<()> {
if candidate_json.is_empty() {
return Ok(());
}
let candidate = serde_json::from_str::<RTCIceCandidateInit>(candidate_json)?;
self.pc.add_ice_candidate(candidate).await?;
Ok(())
}
#[inline]
pub fn session_key(&self) -> &str {
&self.session_key
}
pub async fn wait_connected(&mut self, ms: u64) -> ResultType<()> {
if ms > 0 {
match timeout(Duration::from_millis(ms), self.wait_for_connect_result()).await {
Ok(result) => result?,
Err(_) => return Err(anyhow::anyhow!("WebRTC wait_connected timeout")),
}
} else {
self.wait_for_connect_result().await?;
}
Ok(())
}
/// Explicitly tear down the peer connection.
///
/// Dropping a `WebRTCStream` handle is not enough to release the underlying
/// `RTCPeerConnection`: the global `SESSIONS` map holds a clone, so the pc (and its
/// ICE/DTLS/STUN resources) would stay alive until it happens to reach a terminal ICE
/// state. Closing here fires `on_peer_connection_state_change`, which removes the
/// `SESSIONS` entry, so callers that abandon a stream (e.g. a raced offerer that lost to
/// another transport) should call this to avoid leaking it.
#[inline]
pub async fn close(&self) {
self.pc.close().await.ok();
}
#[inline]
pub fn set_raw(&mut self) {
// not-supported
}
#[inline]
pub fn local_addr(&self) -> SocketAddr {
SocketAddr::new(IpAddr::V4(Ipv4Addr::UNSPECIFIED), 0)
}
#[inline]
pub fn set_send_timeout(&mut self, ms: u64) {
self.send_timeout = ms;
}
#[inline]
pub fn set_key(&mut self, _key: Key) {
// WebRTC traffic is DTLS-encrypted regardless; the secretbox key is unused.
// Callers invoke set_key only after the controller has bound the DTLS fingerprint to the
// verified peer identity (or the controlled side has completed the matching handshake).
// Mark peer-verified so is_secured() matches TCP's post-key-exchange meaning.
self.peer_verified.store(true, Ordering::Release);
}
#[inline]
pub fn is_secured(&self) -> bool {
self.peer_verified.load(Ordering::Acquire)
}
#[inline]
pub async fn send(&mut self, msg: &impl Message) -> ResultType<()> {
self.send_raw(msg.write_to_bytes()?).await
}
#[inline]
pub async fn send_raw(&mut self, msg: Vec<u8>) -> ResultType<()> {
self.send_bytes(Bytes::from(msg)).await
}
#[inline]
async fn wait_for_connect_result(&mut self) -> ResultType<()> {
loop {
match self.state_notify.borrow().clone() {
WebRTCConnectionState::Open => return Ok(()),
WebRTCConnectionState::Closed(reason) => {
return Err(anyhow::anyhow!("WebRTC connection closed: {}", reason));
}
WebRTCConnectionState::Pending => {}
}
self.state_notify.changed().await?;
}
}
/// Fetch (and cache) the detached data channel. `detach()` is idempotent and returns a
/// clone of the same underlying channel, so caching it just avoids re-locking per message.
async fn detached_dc(&self) -> ResultType<Arc<DetachedDataChannel>> {
{
let cache = self.detached.lock().await;
if let Some(dc) = cache.as_ref() {
return Ok(dc.clone());
}
}
let raw = self.stream.lock().await.clone();
let dc = raw.detach().await?;
let mut cache = self.detached.lock().await;
// Another task may have cached it while we were detaching.
if let Some(existing) = cache.as_ref() {
return Ok(existing.clone());
}
*cache = Some(dc.clone());
Ok(dc)
}
pub async fn send_bytes(&mut self, bytes: Bytes) -> ResultType<()> {
let send_timeout = self.send_timeout;
let send_gate = self.send_gate.clone();
// Bound the WHOLE data-channel send (wait-for-open + every write) by send_timeout,
// including time queued behind another clone. Without this a write can park indefinitely
// on SCTP pending-queue backpressure and connection.rs's timeout timer never runs.
if send_timeout > 0 {
let deadline = Instant::now() + Duration::from_millis(send_timeout);
let _send_permit = match timeout_at(deadline, send_gate.acquire_owned()).await {
Ok(Ok(permit)) => permit,
Ok(Err(err)) => {
return Err(Error::new(
ErrorKind::BrokenPipe,
format!("WebRTC send gate closed: {}", err),
)
.into());
}
Err(_) => {
if let Err(err) = self.pc.close().await {
log::warn!("failed to close WebRTC after send timeout: {}", err);
}
return Err(Error::new(ErrorKind::TimedOut, "WebRTC send timeout").into());
}
};
match timeout_at(deadline, self.send_bytes_inner(bytes)).await {
Ok(res) => res,
Err(_) => {
// Keep the logical-message permit while closing so no waiting clone can append
// a new message after a partially-written fragment sequence.
if let Err(err) = self.pc.close().await {
log::warn!("failed to close WebRTC after send timeout: {}", err);
}
Err(Error::new(ErrorKind::TimedOut, "WebRTC send timeout").into())
}
}
} else {
let _send_permit = send_gate.acquire_owned().await.map_err(|err| {
Error::new(
ErrorKind::BrokenPipe,
format!("WebRTC send gate closed: {}", err),
)
})?;
self.send_bytes_inner(bytes).await
}
}
async fn send_bytes_inner(&mut self, bytes: Bytes) -> ResultType<()> {
if bytes.len() > MAX_FRAME_LENGTH {
return Err(Error::new(ErrorKind::InvalidInput, "Overflow").into());
}
self.wait_for_connect_result().await?;
let dc = self.detached_dc().await?;
let data = bytes.as_ref();
let mut offset = 0;
// Always emit at least one fragment (a lone FRAG_END header for an empty message), so a
// zero-length data-channel message — which the receiver cannot distinguish from EOF — is
// never sent.
loop {
let end = (offset + MAX_FRAGMENT_PAYLOAD).min(data.len());
let is_last = end >= data.len();
let chunk = &data[offset..end];
let mut framed = BytesMut::with_capacity(1 + chunk.len());
framed.put_u8(if is_last { FRAG_END } else { FRAG_MORE });
framed.put_slice(chunk);
dc.write(&framed.freeze()).await?;
offset = end;
if is_last {
break;
}
}
Ok(())
}
#[inline]
pub async fn next(&mut self) -> Option<Result<BytesMut, Error>> {
if let Err(err) = self.wait_for_connect_result().await {
self.pc.close().await.ok();
return Some(Err(Error::new(ErrorKind::Other, err.to_string())));
}
let dc = match self.detached_dc().await {
Ok(dc) => dc,
Err(err) => {
self.pc.close().await.ok();
return Some(Err(Error::new(ErrorKind::Other, err.to_string())));
}
};
// Hold recv_state across the reassembly loop: the accumulator must survive `next()`
// cancellation (e.g. next_timeout) so already-read fragments are not lost mid-message.
let mut st = self.recv_state.lock().await;
if st.scratch.len() < RECV_BUF_SIZE {
st.scratch.resize(RECV_BUF_SIZE, 0);
}
loop {
let RecvState { acc, scratch } = &mut *st;
let n = match dc.read(scratch.as_mut_slice()).await {
Ok(n) => n,
Err(err) => {
self.pc.close().await.ok();
return Some(Err(Error::new(
ErrorKind::Other,
format!("data channel read error: {}", err),
)));
}
};
if n == 0 {
// Clean EOF: the remote reset the stream or shut its write half. An empty logical
// message is represented by a 1-byte header, so it is never confused with EOF.
self.pc.close().await.ok();
return None;
}
acc.extend_from_slice(&scratch[1..n]);
// Match TCP's maximum frame size while preventing an unbounded FRAG_MORE stream from
// exhausting memory.
if acc.len() > MAX_FRAME_LENGTH {
acc.clear();
self.pc.close().await.ok();
return Some(Err(Error::new(
ErrorKind::Other,
"WebRTC reassembled message exceeded maximum frame size",
)));
}
if scratch[0] == FRAG_END {
let msg = std::mem::take(acc);
return Some(Ok(msg));
}
}
}
#[inline]
pub async fn next_timeout(&mut self, ms: u64) -> Option<Result<BytesMut, Error>> {
match timeout(Duration::from_millis(ms), self.next()).await {
Ok(res) => res,
Err(_) => None,
}
}
}
pub fn is_webrtc_endpoint(endpoint: &str) -> bool {
// use sdp base64 json string as endpoint, or prefix webrtc:
endpoint.starts_with("webrtc://")
}
#[cfg(test)]
mod tests {
use crate::config;
use crate::webrtc::WebRTCStream;
use crate::webrtc::DEFAULT_ICE_SERVERS;
use std::{sync::Arc, time::Duration};
use tokio::sync::Barrier;
use tokio::time::timeout;
use webrtc::peer_connection::sdp::session_description::RTCSessionDescription;
#[test]
fn test_webrtc_ice_url() {
assert_eq!(
WebRTCStream::get_ice_server_from_url("turn://example.com:3478")
.unwrap_or_default()
.urls[0],
"turn:example.com:3478"
);
assert_eq!(
WebRTCStream::get_ice_server_from_url("turn://example.com")
.unwrap_or_default()
.urls[0],
"turn:example.com:3478"
);
assert_eq!(
WebRTCStream::get_ice_server_from_url("turn://123@example.com")
.unwrap_or_default()
.username,
"123"
);
assert_eq!(
WebRTCStream::get_ice_server_from_url("turn://123@example.com")
.unwrap_or_default()
.credential,
""
);
assert_eq!(
WebRTCStream::get_ice_server_from_url("turn://123:321@example.com")
.unwrap_or_default()
.credential,
"321"
);
assert_eq!(
WebRTCStream::get_ice_server_from_url("stun://example.com:3478")
.unwrap_or_default()
.urls[0],
"stun:example.com:3478"
);
assert_eq!(
WebRTCStream::get_ice_server_from_url("http://123:123@example.com:3478"),
None
);
config::Config::set_option("ice-servers".to_string(), "".to_string());
assert_eq!(
WebRTCStream::get_ice_servers()[0].urls[0],
DEFAULT_ICE_SERVERS[0].to_string()
);
config::Config::set_option(
"ice-servers".to_string(),
",stun://example.com,turn://example.com,sdf".to_string(),
);
assert_eq!(
WebRTCStream::get_ice_servers()[0].urls[0],
"stun:example.com:3478"
);
assert_eq!(
WebRTCStream::get_ice_servers()[1].urls[0],
"turn:example.com:3478"
);
assert_eq!(WebRTCStream::get_ice_servers().len(), 2);
config::Config::set_option(
"ice-servers".to_string(),
"".to_string(),
);
}
#[test]
fn test_webrtc_session_key() {
let mut sdp_str = "".to_owned();
assert_eq!(
WebRTCStream::get_key_for_sdp(
&RTCSessionDescription::offer(sdp_str).unwrap_or_default()
)
.unwrap_or_default(),
""
);
sdp_str = "\
v=0
o=- 7400546379179479477 208696200 IN IP4 0.0.0.0
s=-
t=0 0
a=fingerprint:sha-256 97:52:D6:1F:1E:87:6C:DA:B8:21:95:64:A5:85:89:FA:02:71:C7:4D:B3:FD:25:92:40:FB:6B:65:24:3C:79:88
a=group:BUNDLE 0
a=extmap-allow-mixed
m=application 9 UDP/DTLS/SCTP webrtc-datachannel
c=IN IP4 0.0.0.0
a=setup:actpass
a=mid:0
a=sendrecv
a=sctp-port:5000
a=ice-ufrag:RMWjjpXfpXbDPdMz
a=ice-pwd:BtIqlWHfwhsJdFiBROeLuEbNmYfHxRfT".to_owned();
assert_eq!(
WebRTCStream::get_key_for_sdp(
&RTCSessionDescription::offer(sdp_str).unwrap_or_default()
).unwrap_or_default(),
"sha-256 97:52:D6:1F:1E:87:6C:DA:B8:21:95:64:A5:85:89:FA:02:71:C7:4D:B3:FD:25:92:40:FB:6B:65:24:3C:79:88"
);
sdp_str = "\
v=0
o=- 7400546379179479477 208696200 IN IP4 0.0.0.0
s=-
t=0 0
a=group:BUNDLE 0
a=extmap-allow-mixed
m=application 9 UDP/DTLS/SCTP webrtc-datachannel
c=IN IP4 0.0.0.0
a=fingerprint:sha-256 97:52:D6:1F:1E:87:6C:DA:B8:21:95:64:A5:85:89:FA:02:71:C7:4D:B3:FD:25:92:40:FB:6B:65:24:3C:79:88
a=setup:actpass
a=mid:0
a=sendrecv
a=sctp-port:5000
a=ice-ufrag:RMWjjpXfpXbDPdMz
a=ice-pwd:BtIqlWHfwhsJdFiBROeLuEbNmYfHxRfT".to_owned();
assert_eq!(
WebRTCStream::get_key_for_sdp(
&RTCSessionDescription::offer(sdp_str).unwrap_or_default()
).unwrap_or_default(),
"sha-256 97:52:D6:1F:1E:87:6C:DA:B8:21:95:64:A5:85:89:FA:02:71:C7:4D:B3:FD:25:92:40:FB:6B:65:24:3C:79:88"
);
sdp_str = "\
v=0
o=- 7400546379179479477 208696200 IN IP4 0.0.0.0
s=-
t=0 0
a=group:BUNDLE 0
a=extmap-allow-mixed
m=application 9 UDP/DTLS/SCTP webrtc-datachannel
c=IN IP4 0.0.0.0
a=setup:actpass
a=mid:0
a=sendrecv
a=sctp-port:5000
a=ice-ufrag:RMWjjpXfpXbDPdMz
a=ice-pwd:BtIqlWHfwhsJdFiBROeLuEbNmYfHxRfT"
.to_owned();
assert!(
WebRTCStream::get_key_for_sdp(
&RTCSessionDescription::offer(sdp_str).unwrap_or_default()
)
.is_err(),
"can not find fingerprint attribute"
);
sdp_str = "\
v=0
o=- 7400546379179479477 208696200 IN IP4 0.0.0.0
s=-
t=0 0
a=group:BUNDLE 0
a=extmap-allow-mixed
m=audio 9 UDP/DTLS/SCTP webrtc-datachannel
c=IN IP4 0.0.0.0
a=fingerprint:sha-256 97:52:D6:1F:1E:87:6C:DA:B8:21:95:64:A5:85:89:FA:02:71:C7:4D:B3:FD:25:92:40:FB:6B:65:24:3C:79:88
a=setup:actpass
a=mid:0
a=sendrecv
a=sctp-port:5000
a=ice-ufrag:RMWjjpXfpXbDPdMz
a=ice-pwd:BtIqlWHfwhsJdFiBROeLuEbNmYfHxRfT".to_owned();
assert!(
WebRTCStream::get_key_for_sdp(
&RTCSessionDescription::offer(sdp_str).unwrap_or_default()
)
.is_err(),
"can not find datachannel fingerprint attribute"
);
assert!(
WebRTCStream::get_key_for_sdp(
&RTCSessionDescription::offer("".to_owned()).unwrap_or_default()
)
.is_err(),
"invalid sdp should error"
);
assert!(
WebRTCStream::get_key_for_sdp_json("{}").is_err(),
"empty sdp json should error"
);
assert!(
WebRTCStream::get_key_for_sdp_json("{ss}").is_err(),
"invalid sdp json should error"
);
let endpoint = "webrtc://eyJ0eXBlIjoiYW5zd2VyIiwic2RwIjoidj0wXHJcbm89LSA0MTA1NDk3NTY2NDgyMTQzODEwIDYwMzk1NzQw\
MCBJTiBJUDQgMC4wLjAuMFxyXG5zPS1cclxudD0wIDBcclxuYT1maW5nZXJwcmludDpzaGEtMjU2IDYxOjYwOjc0OjQwOjI4OkNFOjBCOjBDOjc1OjRCOj\
EwOjlBOkVFOjc3OkY1OjQ0OjU3Ojg0OjUxOkRCOjA0OjkyOjRBOjEwOjFDOjRFOjVGOjdFOkYxOkIzOjcxOjIyXHJcbmE9Z3JvdXA6QlVORExFIDBcclxu\
YT1leHRtYXAtYWxsb3ctbWl4ZWRcclxubT1hcHBsaWNhdGlvbiA5IFVEUC9EVExTL1NDVFAgd2VicnRjLWRhdGFjaGFubmVsXHJcbmM9SU4gSVA0IDAuMC\
4wLjBcclxuYT1zZXR1cDphY3RpdmVcclxuYT1taWQ6MFxyXG5hPXNlbmRyZWN2XHJcbmE9c2N0cC1wb3J0OjUwMDBcclxuYT1pY2UtdWZyYWc6SHlnU1Rr\
V2RsRlpHRG1XWlxyXG5hPWljZS1wd2Q6SkJneFZWaGZveVhHdHZha1VWcnBQeHVOSVpMU3llS1pcclxuYT1jYW5kaWRhdGU6OTYzOTg4MzQ4IDEgdWRwID\
IxMzA3MDY0MzEgMTkyLjE2OC4xLjIgNjQwMDcgdHlwIGhvc3RcclxuYT1jYW5kaWRhdGU6OTYzOTg4MzQ4IDIgdWRwIDIxMzA3MDY0MzEgMTkyLjE2OC4x\
LjIgNjQwMDcgdHlwIGhvc3RcclxuYT1jYW5kaWRhdGU6MTg2MTA0NTE5MCAxIHVkcCAxNjk0NDk4ODE1IDE0LjIxMi42OC4xMiAyNzAwNCB0eXAgc3JmbH\
ggcmFkZHIgMC4wLjAuMCBycG9ydCA2NDAwOFxyXG5hPWNhbmRpZGF0ZToxODYxMDQ1MTkwIDIgdWRwIDE2OTQ0OTg4MTUgMTQuMjEyLjY4LjEyIDI3MDA0\
IHR5cCBzcmZseCByYWRkciAwLjAuMC4wIHJwb3J0IDY0MDA4XHJcbmE9ZW5kLW9mLWNhbmRpZGF0ZXNcclxuIn0=".to_owned();
assert_eq!(
WebRTCStream::get_key_for_sdp_json(
&WebRTCStream::get_remote_offer(&endpoint).unwrap_or_default()
).unwrap_or_default(),
"sha-256 61:60:74:40:28:CE:0B:0C:75:4B:10:9A:EE:77:F5:44:57:84:51:DB:04:92:4A:10:1C:4E:5F:7E:F1:B3:71:22"
);
}
#[tokio::test]
async fn test_webrtc_new_stream() {
let mut endpoint = "webrtc://sdfsdf".to_owned();
assert!(
WebRTCStream::new(&endpoint, false, 10000).await.is_err(),
"invalid webrtc endpoint should error"
);
endpoint = "wss://sdfsdf".to_owned();
assert!(
WebRTCStream::new(&endpoint, false, 10000).await.is_err(),
"invalid webrtc endpoint should error"
);
assert!(
WebRTCStream::new("", false, 10000).await.is_ok(),
"local webrtc endpoint should ok"
);
endpoint = "webrtc://eyJ0eXBlIjoiYW5zd2VyIiwic2RwIjoidj0wXHJcbm89LSA0MTA1NDk3NTY2NDgyMTQzODEwIDYwMzk1NzQw\
MCBJTiBJUDQgMC4wLjAuMFxyXG5zPS1cclxudD0wIDBcclxuYT1maW5nZXJwcmludDpzaGEtMjU2IDYxOjYwOjc0OjQwOjI4OkNFOjBCOjBDOjc1OjRCOj\
EwOjlBOkVFOjc3OkY1OjQ0OjU3Ojg0OjUxOkRCOjA0OjkyOjRBOjEwOjFDOjRFOjVGOjdFOkYxOkIzOjcxOjIyXHJcbmE9Z3JvdXA6QlVORExFIDBcclxu\
YT1leHRtYXAtYWxsb3ctbWl4ZWRcclxubT1hcHBsaWNhdGlvbiA5IFVEUC9EVExTL1NDVFAgd2VicnRjLWRhdGFjaGFubmVsXHJcbmM9SU4gSVA0IDAuMC\
4wLjBcclxuYT1zZXR1cDphY3RpdmVcclxuYT1taWQ6MFxyXG5hPXNlbmRyZWN2XHJcbmE9c2N0cC1wb3J0OjUwMDBcclxuYT1pY2UtdWZyYWc6SHlnU1Rr\
V2RsRlpHRG1XWlxyXG5hPWljZS1wd2Q6SkJneFZWaGZveVhHdHZha1VWcnBQeHVOSVpMU3llS1pcclxuYT1jYW5kaWRhdGU6OTYzOTg4MzQ4IDEgdWRwID\
IxMzA3MDY0MzEgMTkyLjE2OC4xLjIgNjQwMDcgdHlwIGhvc3RcclxuYT1jYW5kaWRhdGU6OTYzOTg4MzQ4IDIgdWRwIDIxMzA3MDY0MzEgMTkyLjE2OC4x\
LjIgNjQwMDcgdHlwIGhvc3RcclxuYT1jYW5kaWRhdGU6MTg2MTA0NTE5MCAxIHVkcCAxNjk0NDk4ODE1IDE0LjIxMi42OC4xMiAyNzAwNCB0eXAgc3JmbH\
ggcmFkZHIgMC4wLjAuMCBycG9ydCA2NDAwOFxyXG5hPWNhbmRpZGF0ZToxODYxMDQ1MTkwIDIgdWRwIDE2OTQ0OTg4MTUgMTQuMjEyLjY4LjEyIDI3MDA0\
IHR5cCBzcmZseCByYWRkciAwLjAuMC4wIHJwb3J0IDY0MDA4XHJcbmE9ZW5kLW9mLWNhbmRpZGF0ZXNcclxuIn0=".to_owned();
assert!(
WebRTCStream::new(&endpoint, false, 10000).await.is_err(),
"connect to an 'answer' webrtc endpoint should error"
);
}
#[tokio::test]
async fn test_webrtc_wait_connected_timeout() {
let mut stream = WebRTCStream::new("", false, 100).await.unwrap();
let err = stream.wait_connected(10).await.unwrap_err();
assert!(err.to_string().contains("timeout"));
}
async fn connect_loopback() -> (WebRTCStream, WebRTCStream) {
let mut offerer = WebRTCStream::new("", false, 20000).await.unwrap();
let offer = offerer.get_local_endpoint_trickle().await.unwrap();
let answerer = WebRTCStream::new(&offer, false, 20000).await.unwrap();
let answer = answerer.get_local_endpoint_trickle().await.unwrap();
offerer.set_remote_endpoint(&answer).await.unwrap();
// Bridge trickle candidates directly between the two peers, both directions.
let mut off_ice = offerer.take_local_ice_rx().unwrap();
let mut ans_ice = answerer.take_local_ice_rx().unwrap();
let answerer_for_ice = answerer.clone();
let offerer_for_ice = offerer.clone();
tokio::spawn(async move {
while let Some(c) = off_ice.recv().await {
let _ = answerer_for_ice.add_remote_ice_candidate(&c).await;
}
});
tokio::spawn(async move {
while let Some(c) = ans_ice.recv().await {
let _ = offerer_for_ice.add_remote_ice_candidate(&c).await;
}
});
offerer.wait_connected(20000).await.unwrap();
let mut answerer = answerer;
answerer.wait_connected(20000).await.unwrap();
(offerer, answerer)
}
// One-shot callers exchange only the endpoints and never consume `take_local_ice_rx`.
#[tokio::test]
async fn test_webrtc_loopback_gathered_endpoints() {
let connect = async {
let mut offerer = WebRTCStream::new("", false, 20000).await.unwrap();
let offer = offerer.get_local_endpoint().await.unwrap();
let mut answerer = WebRTCStream::new(&offer, false, 20000).await.unwrap();
let answer = answerer.get_local_endpoint().await.unwrap();
offerer.set_remote_endpoint(&answer).await.unwrap();
offerer.wait_connected(20000).await.unwrap();
answerer.wait_connected(20000).await.unwrap();
offerer.close().await;
answerer.close().await;
};
timeout(Duration::from_secs(40), connect)
.await
.expect("gathered-endpoint WebRTC loopback did not complete in time");
}
// In-process offerer<->answerer loopback exercising the send/next data plane that the framing,
// empty-message, and EOF fixes live in. Connects over host candidates (works offline; any
// configured/default STUN just fails in the background without blocking the host pair).
#[tokio::test]
async fn test_webrtc_loopback_roundtrip() {
let connect = async {
let (mut offerer, mut answerer) = connect_loopback().await;
// Host-candidate loopback is direct, never TURN-relayed.
assert_eq!(offerer.is_relayed().await, Some(false));
// Small message.
offerer.send_raw(b"hello".to_vec()).await.unwrap();
let got = answerer.next().await.unwrap().unwrap();
assert_eq!(&got[..], b"hello");
// Empty message: must round-trip as an empty frame, not be seen as EOF.
offerer.send_raw(Vec::new()).await.unwrap();
let got = answerer.next().await.unwrap().unwrap();
assert_eq!(got.len(), 0, "empty message must not be treated as EOF");
// Payload far above the 64KB single-message cap: must be fragmented and reassembled.
let big = vec![0xABu8; 200_000];
offerer.send_raw(big.clone()).await.unwrap();
let got = answerer.next().await.unwrap().unwrap();
assert_eq!(got.len(), big.len(), "large message must survive fragmentation");
assert_eq!(&got[..], &big[..]);
// Reverse direction.
answerer.send_raw(b"world".to_vec()).await.unwrap();
let got = offerer.next().await.unwrap().unwrap();
assert_eq!(&got[..], b"world");
// Peer close: the other side observes a clean EOF (None) or a close error, never a hang.
offerer.close().await;
match timeout(Duration::from_secs(10), answerer.next()).await {
Ok(None) | Ok(Some(Err(_))) => {}
Ok(Some(Ok(b))) => panic!("expected EOF after peer close, got {} bytes", b.len()),
Err(_) => panic!("answerer.next() hung after peer close"),
}
answerer.close().await;
};
timeout(Duration::from_secs(40), connect)
.await
.expect("webrtc loopback did not complete in time");
}
#[tokio::test]
async fn test_webrtc_concurrent_large_sends_preserve_boundaries() {
let connect = async {
let (offerer, mut answerer) = connect_loopback().await;
let mut sender_a = offerer.clone();
let mut sender_b = offerer.clone();
let expected_a = vec![0xAA; 200_000];
let expected_b = vec![0xBB; 200_000];
let payload_a = expected_a.clone();
let payload_b = expected_b.clone();
let barrier = Arc::new(Barrier::new(3));
let barrier_a = barrier.clone();
let send_a = tokio::spawn(async move {
barrier_a.wait().await;
sender_a.send_raw(payload_a).await
});
let barrier_b = barrier.clone();
let send_b = tokio::spawn(async move {
barrier_b.wait().await;
sender_b.send_raw(payload_b).await
});
barrier.wait().await;
let receive = async {
let first = answerer.next().await.unwrap().unwrap();
let second = answerer.next().await.unwrap().unwrap();
(first, second)
};
let (send_a, send_b, (first, second)) = tokio::join!(send_a, send_b, receive);
send_a.unwrap().unwrap();
send_b.unwrap().unwrap();
let boundaries_preserved = (first.as_ref() == expected_a.as_slice()
&& second.as_ref() == expected_b.as_slice())
|| (first.as_ref() == expected_b.as_slice()
&& second.as_ref() == expected_a.as_slice());
assert!(boundaries_preserved, "concurrent messages were interleaved");
offerer.close().await;
answerer.close().await;
};
timeout(Duration::from_secs(40), connect)
.await
.expect("concurrent WebRTC sends did not complete in time");
}
}