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use super::{
AsyncRead, AsyncWrite, Buffer, Context, End, ErrorKind, H3BodyFrameType, Pin, Ready,
ReceivedBody, ReceivedBodyState, StateOutput, io, ready,
};
use crate::{
Headers,
h3::{Frame, FrameDecodeError, H3ErrorCode},
headers::qpack::FieldSection,
};
#[cfg(test)]
mod tests;
impl<Transport> ReceivedBody<'_, Transport>
where
Transport: AsyncRead + AsyncWrite + Unpin + Send + Sync + 'static,
{
#[inline]
#[allow(
clippy::too_many_arguments,
clippy::too_many_lines,
reason = "internal api, will revisit later"
)]
pub(super) fn handle_h3_data(
&mut self,
cx: &mut Context<'_>,
buf: &mut [u8],
remaining_in_frame: u64,
total: u64,
frame_type: H3BodyFrameType,
partial_frame_header: bool,
) -> StateOutput {
if partial_frame_header {
let transport = self
.transport
.as_deref_mut()
.ok_or_else(|| io::Error::from(ErrorKind::NotConnected))?;
let bytes = ready!(Pin::new(transport).poll_read(cx, buf))?;
if bytes == 0 {
return Ready(Err(io::Error::from(ErrorKind::UnexpectedEof)));
}
self.buffer.extend_from_slice(&buf[..bytes]);
// Try to decode the frame header from the reassembled buffer
let (remaining_in_frame, frame_type, consumed) = match Frame::decode(&self.buffer) {
Ok((Frame::Data(len), consumed)) => (len, H3BodyFrameType::Data, consumed),
Ok((Frame::Headers(len), consumed)) => (len, H3BodyFrameType::Trailers, consumed),
Ok((Frame::Unknown(len), consumed)) => (len, H3BodyFrameType::Unknown, consumed),
Err(FrameDecodeError::Incomplete) => {
// Still not enough bytes — stay in partial state
return Ready(Ok((
ReceivedBodyState::H3Data {
remaining_in_frame: 0,
total,
frame_type: H3BodyFrameType::Start,
partial_frame_header: true,
},
0,
)));
}
Err(FrameDecodeError::Error(_)) => {
return Ready(Err(io::Error::new(
ErrorKind::InvalidData,
"H3 frame error",
)));
}
Ok(_err) => {
return Ready(Err(io::Error::new(
ErrorKind::InvalidData,
"Unexpected frame type on request stream",
)));
}
};
self.buffer.ignore_front(consumed);
if frame_type == H3BodyFrameType::Trailers
&& remaining_in_frame > self.h3_max_field_section_size
{
return Ready(Err(io::Error::other(H3ErrorCode::MessageError)));
}
let leftover = self.buffer.len();
if leftover == 0 {
// Frame header decoded but no payload bytes yet
return Ready(Ok((
ReceivedBodyState::H3Data {
remaining_in_frame,
total,
frame_type,
partial_frame_header: false,
},
0,
)));
}
// Copy leftover payload bytes from self.buffer into buf
buf[..leftover].copy_from_slice(&self.buffer);
self.buffer.ignore_front(leftover);
Ready(
H3Frame {
self_buffer: &mut self.buffer,
remaining_in_frame,
total,
frame_type,
buf: &mut buf[..leftover],
content_length: self.content_length,
max_len: self.max_len,
max_trailer_size: self.h3_max_field_section_size,
trailers: &mut self.trailers,
}
.decode(),
)
} else {
let bytes = ready!(self.read_raw(cx, buf)?);
if bytes == 0 {
return if let Some(expected) = self.content_length
&& total != expected
{
Ready(Err(io::Error::new(
ErrorKind::InvalidData,
format!("content-length mismatch, {expected} != {total}"),
)))
} else {
Ready(Ok((End, 0)))
};
}
Ready(
H3Frame {
self_buffer: &mut self.buffer,
remaining_in_frame,
total,
frame_type,
buf: &mut buf[..bytes],
content_length: self.content_length,
max_len: self.max_len,
max_trailer_size: self.h3_max_field_section_size,
trailers: &mut self.trailers,
}
.decode(),
)
}
}
}
struct H3Frame<'a> {
self_buffer: &'a mut Buffer,
remaining_in_frame: u64,
total: u64,
frame_type: H3BodyFrameType,
buf: &'a mut [u8],
content_length: Option<u64>,
max_len: u64,
max_trailer_size: u64,
trailers: &'a mut Option<Headers>,
}
impl H3Frame<'_> {
#[allow(clippy::too_many_lines, reason = "internal api, will revisit later")]
fn decode(self) -> io::Result<(ReceivedBodyState, usize)> {
let Self {
self_buffer,
mut remaining_in_frame,
mut total,
mut frame_type,
buf,
content_length,
max_len,
max_trailer_size,
trailers,
} = self;
if buf.is_empty() {
return Err(io::Error::from(ErrorKind::UnexpectedEof));
}
let mut ranges_to_keep = vec![];
let mut pos = 0usize;
let state = loop {
// Consume bytes from the current frame
if remaining_in_frame > 0 {
let available = buf.len() - pos;
let consume =
available.min(usize::try_from(remaining_in_frame).unwrap_or(usize::MAX));
match frame_type {
H3BodyFrameType::Data => {
ranges_to_keep.push(pos..pos + consume);
total += consume as u64;
if total > max_len {
return Err(io::Error::new(ErrorKind::Unsupported, "content too long"));
}
if let Some(expected) = content_length
&& total > expected
{
return Err(io::Error::new(
ErrorKind::InvalidData,
format!("body exceeds content-length, {total} > {expected}"),
));
}
}
H3BodyFrameType::Trailers => {
self_buffer.extend_from_slice(&buf[pos..pos + consume]);
}
_ => {}
}
pos += consume;
remaining_in_frame -= consume as u64;
// If we finished a trailers frame, body is done
if remaining_in_frame == 0 && frame_type == H3BodyFrameType::Trailers {
// RFC 9114 §4.1.1: pseudo-headers MUST NOT appear in trailers.
// We permissively ignore them rather than failing the request.
*trailers = Some(
FieldSection::decode(&self_buffer[..])
.map_err(|_| {
io::Error::new(
ErrorKind::InvalidData,
"invalid trailer field section",
)
})?
.into_headers()
.into_owned(),
);
self_buffer.truncate(0);
if let Some(expected) = content_length
&& total != expected
{
return Err(io::Error::new(
ErrorKind::InvalidData,
"content-length mismatch",
));
}
break End;
}
}
// If we've consumed the whole buffer, done for this read
if pos >= buf.len() {
break ReceivedBodyState::H3Data {
remaining_in_frame,
total,
frame_type,
partial_frame_header: false,
};
}
// Decode next frame header
match Frame::decode(&buf[pos..]) {
Ok((Frame::Data(len), consumed)) => {
pos += consumed;
remaining_in_frame = len;
frame_type = H3BodyFrameType::Data;
}
Ok((Frame::Headers(len), consumed)) => {
if len > max_trailer_size {
return Err(io::Error::other(H3ErrorCode::MessageError));
}
pos += consumed;
remaining_in_frame = len;
frame_type = H3BodyFrameType::Trailers;
}
Ok((Frame::Unknown(len), consumed)) => {
pos += consumed;
remaining_in_frame = len;
frame_type = H3BodyFrameType::Unknown;
}
Err(FrameDecodeError::Incomplete) => {
self_buffer.extend_from_slice(&buf[pos..]);
break ReceivedBodyState::H3Data {
remaining_in_frame: 0,
total,
frame_type: H3BodyFrameType::Start,
partial_frame_header: true,
};
}
Err(FrameDecodeError::Error(_code)) => {
return Err(io::Error::new(ErrorKind::InvalidData, "H3 frame error"));
}
Ok(_) => {
return Err(io::Error::new(
ErrorKind::InvalidData,
"unexpected frame type on request stream",
));
}
}
};
// Compact: squeeze out non-body bytes
let mut bytes = 0;
for range in ranges_to_keep {
let len = range.end - range.start;
buf.copy_within(range, bytes);
bytes += len;
}
Ok((state, bytes))
}
}