Adding upstream version 115.7.0esr.upstream/115.7.0esr

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 565 insertions, 0 deletions

diff --git a/third_party/rust/h2/src/proto/streams/send.rs b/third_party/rust/h2/src/proto/streams/send.rs
new file mode 100644
index 0000000000..2c5a38c801
--- /dev/null
+++ b/third_party/rust/h2/src/proto/streams/send.rs
@@ -0,0 +1,565 @@
+use super::{
+    store, Buffer, Codec, Config, Counts, Frame, Prioritize, Prioritized, Store, Stream, StreamId,
+    StreamIdOverflow, WindowSize,
+};
+use crate::codec::UserError;
+use crate::frame::{self, Reason};
+use crate::proto::{Error, Initiator};
+
+use bytes::Buf;
+use http;
+use std::task::{Context, Poll, Waker};
+use tokio::io::AsyncWrite;
+
+use std::io;
+
+/// Manages state transitions related to outbound frames.
+#[derive(Debug)]
+pub(super) struct Send {
+    /// Stream identifier to use for next initialized stream.
+    next_stream_id: Result<StreamId, StreamIdOverflow>,
+
+    /// Any streams with a higher ID are ignored.
+    ///
+    /// This starts as MAX, but is lowered when a GOAWAY is received.
+    ///
+    /// > After sending a GOAWAY frame, the sender can discard frames for
+    /// > streams initiated by the receiver with identifiers higher than
+    /// > the identified last stream.
+    max_stream_id: StreamId,
+
+    /// Initial window size of locally initiated streams
+    init_window_sz: WindowSize,
+
+    /// Prioritization layer
+    prioritize: Prioritize,
+
+    is_push_enabled: bool,
+
+    /// If extended connect protocol is enabled.
+    is_extended_connect_protocol_enabled: bool,
+}
+
+/// A value to detect which public API has called `poll_reset`.
+#[derive(Debug)]
+pub(crate) enum PollReset {
+    AwaitingHeaders,
+    Streaming,
+}
+
+impl Send {
+    /// Create a new `Send`
+    pub fn new(config: &Config) -> Self {
+        Send {
+            init_window_sz: config.remote_init_window_sz,
+            max_stream_id: StreamId::MAX,
+            next_stream_id: Ok(config.local_next_stream_id),
+            prioritize: Prioritize::new(config),
+            is_push_enabled: true,
+            is_extended_connect_protocol_enabled: false,
+        }
+    }
+
+    /// Returns the initial send window size
+    pub fn init_window_sz(&self) -> WindowSize {
+        self.init_window_sz
+    }
+
+    pub fn open(&mut self) -> Result<StreamId, UserError> {
+        let stream_id = self.ensure_next_stream_id()?;
+        self.next_stream_id = stream_id.next_id();
+        Ok(stream_id)
+    }
+
+    pub fn reserve_local(&mut self) -> Result<StreamId, UserError> {
+        let stream_id = self.ensure_next_stream_id()?;
+        self.next_stream_id = stream_id.next_id();
+        Ok(stream_id)
+    }
+
+    fn check_headers(fields: &http::HeaderMap) -> Result<(), UserError> {
+        // 8.1.2.2. Connection-Specific Header Fields
+        if fields.contains_key(http::header::CONNECTION)
+            || fields.contains_key(http::header::TRANSFER_ENCODING)
+            || fields.contains_key(http::header::UPGRADE)
+            || fields.contains_key("keep-alive")
+            || fields.contains_key("proxy-connection")
+        {
+            tracing::debug!("illegal connection-specific headers found");
+            return Err(UserError::MalformedHeaders);
+        } else if let Some(te) = fields.get(http::header::TE) {
+            if te != "trailers" {
+                tracing::debug!("illegal connection-specific headers found");
+                return Err(UserError::MalformedHeaders);
+            }
+        }
+        Ok(())
+    }
+
+    pub fn send_push_promise<B>(
+        &mut self,
+        frame: frame::PushPromise,
+        buffer: &mut Buffer<Frame<B>>,
+        stream: &mut store::Ptr,
+        task: &mut Option<Waker>,
+    ) -> Result<(), UserError> {
+        if !self.is_push_enabled {
+            return Err(UserError::PeerDisabledServerPush);
+        }
+
+        tracing::trace!(
+            "send_push_promise; frame={:?}; init_window={:?}",
+            frame,
+            self.init_window_sz
+        );
+
+        Self::check_headers(frame.fields())?;
+
+        // Queue the frame for sending
+        self.prioritize
+            .queue_frame(frame.into(), buffer, stream, task);
+
+        Ok(())
+    }
+
+    pub fn send_headers<B>(
+        &mut self,
+        frame: frame::Headers,
+        buffer: &mut Buffer<Frame<B>>,
+        stream: &mut store::Ptr,
+        counts: &mut Counts,
+        task: &mut Option<Waker>,
+    ) -> Result<(), UserError> {
+        tracing::trace!(
+            "send_headers; frame={:?}; init_window={:?}",
+            frame,
+            self.init_window_sz
+        );
+
+        Self::check_headers(frame.fields())?;
+
+        let end_stream = frame.is_end_stream();
+
+        // Update the state
+        stream.state.send_open(end_stream)?;
+
+        if counts.peer().is_local_init(frame.stream_id()) {
+            // If we're waiting on a PushPromise anyway
+            // handle potentially queueing the stream at that point
+            if !stream.is_pending_push {
+                if counts.can_inc_num_send_streams() {
+                    counts.inc_num_send_streams(stream);
+                } else {
+                    self.prioritize.queue_open(stream);
+                }
+            }
+        }
+
+        // Queue the frame for sending
+        self.prioritize
+            .queue_frame(frame.into(), buffer, stream, task);
+
+        Ok(())
+    }
+
+    /// Send an explicit RST_STREAM frame
+    pub fn send_reset<B>(
+        &mut self,
+        reason: Reason,
+        initiator: Initiator,
+        buffer: &mut Buffer<Frame<B>>,
+        stream: &mut store::Ptr,
+        counts: &mut Counts,
+        task: &mut Option<Waker>,
+    ) {
+        let is_reset = stream.state.is_reset();
+        let is_closed = stream.state.is_closed();
+        let is_empty = stream.pending_send.is_empty();
+        let stream_id = stream.id;
+
+        tracing::trace!(
+            "send_reset(..., reason={:?}, initiator={:?}, stream={:?}, ..., \
+             is_reset={:?}; is_closed={:?}; pending_send.is_empty={:?}; \
+             state={:?} \
+             ",
+            reason,
+            initiator,
+            stream_id,
+            is_reset,
+            is_closed,
+            is_empty,
+            stream.state
+        );
+
+        if is_reset {
+            // Don't double reset
+            tracing::trace!(
+                " -> not sending RST_STREAM ({:?} is already reset)",
+                stream_id
+            );
+            return;
+        }
+
+        // Transition the state to reset no matter what.
+        stream.state.set_reset(stream_id, reason, initiator);
+
+        // If closed AND the send queue is flushed, then the stream cannot be
+        // reset explicitly, either. Implicit resets can still be queued.
+        if is_closed && is_empty {
+            tracing::trace!(
+                " -> not sending explicit RST_STREAM ({:?} was closed \
+                 and send queue was flushed)",
+                stream_id
+            );
+            return;
+        }
+
+        // Clear all pending outbound frames.
+        // Note that we don't call `self.recv_err` because we want to enqueue
+        // the reset frame before transitioning the stream inside
+        // `reclaim_all_capacity`.
+        self.prioritize.clear_queue(buffer, stream);
+
+        let frame = frame::Reset::new(stream.id, reason);
+
+        tracing::trace!("send_reset -- queueing; frame={:?}", frame);
+        self.prioritize
+            .queue_frame(frame.into(), buffer, stream, task);
+        self.prioritize.reclaim_all_capacity(stream, counts);
+    }
+
+    pub fn schedule_implicit_reset(
+        &mut self,
+        stream: &mut store::Ptr,
+        reason: Reason,
+        counts: &mut Counts,
+        task: &mut Option<Waker>,
+    ) {
+        if stream.state.is_closed() {
+            // Stream is already closed, nothing more to do
+            return;
+        }
+
+        stream.state.set_scheduled_reset(reason);
+
+        self.prioritize.reclaim_reserved_capacity(stream, counts);
+        self.prioritize.schedule_send(stream, task);
+    }
+
+    pub fn send_data<B>(
+        &mut self,
+        frame: frame::Data<B>,
+        buffer: &mut Buffer<Frame<B>>,
+        stream: &mut store::Ptr,
+        counts: &mut Counts,
+        task: &mut Option<Waker>,
+    ) -> Result<(), UserError>
+    where
+        B: Buf,
+    {
+        self.prioritize
+            .send_data(frame, buffer, stream, counts, task)
+    }
+
+    pub fn send_trailers<B>(
+        &mut self,
+        frame: frame::Headers,
+        buffer: &mut Buffer<Frame<B>>,
+        stream: &mut store::Ptr,
+        counts: &mut Counts,
+        task: &mut Option<Waker>,
+    ) -> Result<(), UserError> {
+        // TODO: Should this logic be moved into state.rs?
+        if !stream.state.is_send_streaming() {
+            return Err(UserError::UnexpectedFrameType);
+        }
+
+        stream.state.send_close();
+
+        tracing::trace!("send_trailers -- queuing; frame={:?}", frame);
+        self.prioritize
+            .queue_frame(frame.into(), buffer, stream, task);
+
+        // Release any excess capacity
+        self.prioritize.reserve_capacity(0, stream, counts);
+
+        Ok(())
+    }
+
+    pub fn poll_complete<T, B>(
+        &mut self,
+        cx: &mut Context,
+        buffer: &mut Buffer<Frame<B>>,
+        store: &mut Store,
+        counts: &mut Counts,
+        dst: &mut Codec<T, Prioritized<B>>,
+    ) -> Poll<io::Result<()>>
+    where
+        T: AsyncWrite + Unpin,
+        B: Buf,
+    {
+        self.prioritize
+            .poll_complete(cx, buffer, store, counts, dst)
+    }
+
+    /// Request capacity to send data
+    pub fn reserve_capacity(
+        &mut self,
+        capacity: WindowSize,
+        stream: &mut store::Ptr,
+        counts: &mut Counts,
+    ) {
+        self.prioritize.reserve_capacity(capacity, stream, counts)
+    }
+
+    pub fn poll_capacity(
+        &mut self,
+        cx: &Context,
+        stream: &mut store::Ptr,
+    ) -> Poll<Option<Result<WindowSize, UserError>>> {
+        if !stream.state.is_send_streaming() {
+            return Poll::Ready(None);
+        }
+
+        if !stream.send_capacity_inc {
+            stream.wait_send(cx);
+            return Poll::Pending;
+        }
+
+        stream.send_capacity_inc = false;
+
+        Poll::Ready(Some(Ok(self.capacity(stream))))
+    }
+
+    /// Current available stream send capacity
+    pub fn capacity(&self, stream: &mut store::Ptr) -> WindowSize {
+        let available = stream.send_flow.available().as_size() as usize;
+        let buffered = stream.buffered_send_data;
+
+        available
+            .min(self.prioritize.max_buffer_size())
+            .saturating_sub(buffered) as WindowSize
+    }
+
+    pub fn poll_reset(
+        &self,
+        cx: &Context,
+        stream: &mut Stream,
+        mode: PollReset,
+    ) -> Poll<Result<Reason, crate::Error>> {
+        match stream.state.ensure_reason(mode)? {
+            Some(reason) => Poll::Ready(Ok(reason)),
+            None => {
+                stream.wait_send(cx);
+                Poll::Pending
+            }
+        }
+    }
+
+    pub fn recv_connection_window_update(
+        &mut self,
+        frame: frame::WindowUpdate,
+        store: &mut Store,
+        counts: &mut Counts,
+    ) -> Result<(), Reason> {
+        self.prioritize
+            .recv_connection_window_update(frame.size_increment(), store, counts)
+    }
+
+    pub fn recv_stream_window_update<B>(
+        &mut self,
+        sz: WindowSize,
+        buffer: &mut Buffer<Frame<B>>,
+        stream: &mut store::Ptr,
+        counts: &mut Counts,
+        task: &mut Option<Waker>,
+    ) -> Result<(), Reason> {
+        if let Err(e) = self.prioritize.recv_stream_window_update(sz, stream) {
+            tracing::debug!("recv_stream_window_update !!; err={:?}", e);
+
+            self.send_reset(
+                Reason::FLOW_CONTROL_ERROR,
+                Initiator::Library,
+                buffer,
+                stream,
+                counts,
+                task,
+            );
+
+            return Err(e);
+        }
+
+        Ok(())
+    }
+
+    pub(super) fn recv_go_away(&mut self, last_stream_id: StreamId) -> Result<(), Error> {
+        if last_stream_id > self.max_stream_id {
+            // The remote endpoint sent a `GOAWAY` frame indicating a stream
+            // that we never sent, or that we have already terminated on account
+            // of previous `GOAWAY` frame. In either case, that is illegal.
+            // (When sending multiple `GOAWAY`s, "Endpoints MUST NOT increase
+            // the value they send in the last stream identifier, since the
+            // peers might already have retried unprocessed requests on another
+            // connection.")
+            proto_err!(conn:
+                "recv_go_away: last_stream_id ({:?}) > max_stream_id ({:?})",
+                last_stream_id, self.max_stream_id,
+            );
+            return Err(Error::library_go_away(Reason::PROTOCOL_ERROR));
+        }
+
+        self.max_stream_id = last_stream_id;
+        Ok(())
+    }
+
+    pub fn handle_error<B>(
+        &mut self,
+        buffer: &mut Buffer<Frame<B>>,
+        stream: &mut store::Ptr,
+        counts: &mut Counts,
+    ) {
+        // Clear all pending outbound frames
+        self.prioritize.clear_queue(buffer, stream);
+        self.prioritize.reclaim_all_capacity(stream, counts);
+    }
+
+    pub fn apply_remote_settings<B>(
+        &mut self,
+        settings: &frame::Settings,
+        buffer: &mut Buffer<Frame<B>>,
+        store: &mut Store,
+        counts: &mut Counts,
+        task: &mut Option<Waker>,
+    ) -> Result<(), Error> {
+        if let Some(val) = settings.is_extended_connect_protocol_enabled() {
+            self.is_extended_connect_protocol_enabled = val;
+        }
+
+        // Applies an update to the remote endpoint's initial window size.
+        //
+        // Per RFC 7540 §6.9.2:
+        //
+        // In addition to changing the flow-control window for streams that are
+        // not yet active, a SETTINGS frame can alter the initial flow-control
+        // window size for streams with active flow-control windows (that is,
+        // streams in the "open" or "half-closed (remote)" state). When the
+        // value of SETTINGS_INITIAL_WINDOW_SIZE changes, a receiver MUST adjust
+        // the size of all stream flow-control windows that it maintains by the
+        // difference between the new value and the old value.
+        //
+        // A change to `SETTINGS_INITIAL_WINDOW_SIZE` can cause the available
+        // space in a flow-control window to become negative. A sender MUST
+        // track the negative flow-control window and MUST NOT send new
+        // flow-controlled frames until it receives WINDOW_UPDATE frames that
+        // cause the flow-control window to become positive.
+        if let Some(val) = settings.initial_window_size() {
+            let old_val = self.init_window_sz;
+            self.init_window_sz = val;
+
+            if val < old_val {
+                // We must decrease the (remote) window on every open stream.
+                let dec = old_val - val;
+                tracing::trace!("decrementing all windows; dec={}", dec);
+
+                let mut total_reclaimed = 0;
+                store.for_each(|mut stream| {
+                    let stream = &mut *stream;
+
+                    stream.send_flow.dec_send_window(dec);
+
+                    // It's possible that decreasing the window causes
+                    // `window_size` (the stream-specific window) to fall below
+                    // `available` (the portion of the connection-level window
+                    // that we have allocated to the stream).
+                    // In this case, we should take that excess allocation away
+                    // and reassign it to other streams.
+                    let window_size = stream.send_flow.window_size();
+                    let available = stream.send_flow.available().as_size();
+                    let reclaimed = if available > window_size {
+                        // Drop down to `window_size`.
+                        let reclaim = available - window_size;
+                        stream.send_flow.claim_capacity(reclaim);
+                        total_reclaimed += reclaim;
+                        reclaim
+                    } else {
+                        0
+                    };
+
+                    tracing::trace!(
+                        "decremented stream window; id={:?}; decr={}; reclaimed={}; flow={:?}",
+                        stream.id,
+                        dec,
+                        reclaimed,
+                        stream.send_flow
+                    );
+
+                    // TODO: Should this notify the producer when the capacity
+                    // of a stream is reduced? Maybe it should if the capacity
+                    // is reduced to zero, allowing the producer to stop work.
+                });
+
+                self.prioritize
+                    .assign_connection_capacity(total_reclaimed, store, counts);
+            } else if val > old_val {
+                let inc = val - old_val;
+
+                store.try_for_each(|mut stream| {
+                    self.recv_stream_window_update(inc, buffer, &mut stream, counts, task)
+                        .map_err(Error::library_go_away)
+                })?;
+            }
+        }
+
+        if let Some(val) = settings.is_push_enabled() {
+            self.is_push_enabled = val
+        }
+
+        Ok(())
+    }
+
+    pub fn clear_queues(&mut self, store: &mut Store, counts: &mut Counts) {
+        self.prioritize.clear_pending_capacity(store, counts);
+        self.prioritize.clear_pending_send(store, counts);
+        self.prioritize.clear_pending_open(store, counts);
+    }
+
+    pub fn ensure_not_idle(&self, id: StreamId) -> Result<(), Reason> {
+        if let Ok(next) = self.next_stream_id {
+            if id >= next {
+                return Err(Reason::PROTOCOL_ERROR);
+            }
+        }
+        // if next_stream_id is overflowed, that's ok.
+
+        Ok(())
+    }
+
+    pub fn ensure_next_stream_id(&self) -> Result<StreamId, UserError> {
+        self.next_stream_id
+            .map_err(|_| UserError::OverflowedStreamId)
+    }
+
+    pub fn may_have_created_stream(&self, id: StreamId) -> bool {
+        if let Ok(next_id) = self.next_stream_id {
+            // Peer::is_local_init should have been called beforehand
+            debug_assert_eq!(id.is_server_initiated(), next_id.is_server_initiated(),);
+            id < next_id
+        } else {
+            true
+        }
+    }
+
+    pub(super) fn maybe_reset_next_stream_id(&mut self, id: StreamId) {
+        if let Ok(next_id) = self.next_stream_id {
+            // Peer::is_local_init should have been called beforehand
+            debug_assert_eq!(id.is_server_initiated(), next_id.is_server_initiated());
+            if id >= next_id {
+                self.next_stream_id = id.next_id();
+            }
+        }
+    }
+
+    pub(crate) fn is_extended_connect_protocol_enabled(&self) -> bool {
+        self.is_extended_connect_protocol_enabled
+    }
+}