refactor(error): add header parse error details in hyper::Error

When a header parse error is because of content-length or transfer-encoding semantics, include a better error message in the `hyper::Error`.

Author: seanmonstar

src/error.rs

@@ -72,13 +72,24 @@ pub(super) enum Parse {
  #[cfg(feature = "http1")]
  VersionH2,
  Uri,
- Header,
+ Header(Header),
  TooLarge,
  Status,
  #[cfg_attr(debug_assertions, allow(unused))]
  Internal,
 }
 
+#[derive(Debug)]
+pub(super) enum Header {
+ Token,
+ #[cfg(feature = "http1")]
+ ContentLengthInvalid,
+ #[cfg(feature = "http1")]
+ TransferEncodingInvalid,
+ #[cfg(feature = "http1")]
+ TransferEncodingUnexpected,
+}
+
 #[derive(Debug)]
 pub(super) enum User {
  /// Error calling user's HttpBody::poll_data().
@@ -375,7 +386,19 @@ impl Error {
  #[cfg(feature = "http1")]
  Kind::Parse(Parse::VersionH2) => "invalid HTTP version parsed (found HTTP2 preface)",
  Kind::Parse(Parse::Uri) => "invalid URI",
- Kind::Parse(Parse::Header) => "invalid HTTP header parsed",
+ Kind::Parse(Parse::Header(Header::Token)) => "invalid HTTP header parsed",
+ #[cfg(feature = "http1")]
+ Kind::Parse(Parse::Header(Header::ContentLengthInvalid)) => {
+ "invalid content-length parsed"
+ }
+ #[cfg(feature = "http1")]
+ Kind::Parse(Parse::Header(Header::TransferEncodingInvalid)) => {
+ "invalid transfer-encoding parsed"
+ }
+ #[cfg(feature = "http1")]
+ Kind::Parse(Parse::Header(Header::TransferEncodingUnexpected)) => {
+ "unexpected transfer-encoding parsed"
+ }
  Kind::Parse(Parse::TooLarge) => "message head is too large",
  Kind::Parse(Parse::Status) => "invalid HTTP status-code parsed",
  Kind::Parse(Parse::Internal) => {
@@ -475,13 +498,28 @@ impl From<Parse> for Error {
  }
 }
 
+#[cfg(feature = "http1")]
+impl Parse {
+ pub(crate) fn content_length_invalid() -> Self {
+ Parse::Header(Header::ContentLengthInvalid)
+ }
+
+ pub(crate) fn transfer_encoding_invalid() -> Self {
+ Parse::Header(Header::TransferEncodingInvalid)
+ }
+
+ pub(crate) fn transfer_encoding_unexpected() -> Self {
+ Parse::Header(Header::TransferEncodingUnexpected)
+ }
+}
+
 impl From<httparse::Error> for Parse {
  fn from(err: httparse::Error) -> Parse {
  match err {
  httparse::Error::HeaderName
  | httparse::Error::HeaderValue
  | httparse::Error::NewLine
- | httparse::Error::Token => Parse::Header,
+ | httparse::Error::Token => Parse::Header(Header::Token),
  httparse::Error::Status => Parse::Status,
  httparse::Error::TooManyHeaders => Parse::TooLarge,
  httparse::Error::Version => Parse::Version,

src/proto/h1/role.rs

@@ -205,7 +205,7 @@ impl Http1Transaction for Server {
  // malformed. A server should respond with 400 Bad Request.
  if !is_http_11 {
  debug!("HTTP/1.0 cannot have Transfer-Encoding header");
- return Err(Parse::Header);
+ return Err(Parse::transfer_encoding_unexpected());
  }
  is_te = true;
  if headers::is_chunked_(&value) {
@@ -221,15 +221,15 @@ impl Http1Transaction for Server {
  }
  let len = value
  .to_str()
- .map_err(|_| Parse::Header)
- .and_then(|s| s.parse().map_err(|_| Parse::Header))?;
+ .map_err(|_| Parse::content_length_invalid())
+ .and_then(|s| s.parse().map_err(|_| Parse::content_length_invalid()))?;
  if let Some(prev) = con_len {
  if prev != len {
  debug!(
  "multiple Content-Length headers with different values: [{}, {}]",
  prev, len,
  );
- return Err(Parse::Header);
+ return Err(Parse::content_length_invalid());
  }
  // we don't need to append this secondary length
  continue;
@@ -267,7 +267,7 @@ impl Http1Transaction for Server {
 
  if is_te && !is_te_chunked {
  debug!("request with transfer-encoding header, but not chunked, bad request");
- return Err(Parse::Header);
+ return Err(Parse::transfer_encoding_invalid());
  }
 
  let mut extensions = http::Extensions::default();
@@ -386,7 +386,7 @@ impl Http1Transaction for Server {
  use crate::error::Kind;
  let status = match *err.kind() {
  Kind::Parse(Parse::Method)
- | Kind::Parse(Parse::Header)
+ | Kind::Parse(Parse::Header(_))
  | Kind::Parse(Parse::Uri)
  | Kind::Parse(Parse::Version) => StatusCode::BAD_REQUEST,
  Kind::Parse(Parse::TooLarge) => StatusCode::REQUEST_HEADER_FIELDS_TOO_LARGE,
@@ -1106,7 +1106,7 @@ impl Client {
  // malformed. A server should respond with 400 Bad Request.
  if inc.version == Version::HTTP_10 {
  debug!("HTTP/1.0 cannot have Transfer-Encoding header");
- Err(Parse::Header)
+ Err(Parse::transfer_encoding_unexpected())
  } else if headers::transfer_encoding_is_chunked(&inc.headers) {
  Ok(Some((DecodedLength::CHUNKED, false)))
  } else {
@@ -1117,7 +1117,7 @@ impl Client {
  Ok(Some((DecodedLength::checked_new(len)?, false)))
  } else if inc.headers.contains_key(header::CONTENT_LENGTH) {
  debug!("illegal Content-Length header");
- Err(Parse::Header)
+ Err(Parse::content_length_invalid())
  } else {
  trace!("neither Transfer-Encoding nor Content-Length");
  Ok(Some((DecodedLength::CLOSE_DELIMITED, false)))