Enum RejectReason 

pub enum RejectReason {
    NotTls,
    MalformedRecord,
    MalformedHandshake,
    Fragmented,
    TooLarge,
    NoSni,
    EchOuterAbsent,
    SniUnmatched,
    AlpnUnmatched,
    ProxyHeaderInvalid,
    FrontClosed,
}

Why a preread attempt was terminally rejected.

Variants

NotTls

The first TLS record’s ContentType was not handshake (22).

MalformedRecord

A TLS record’s framing is invalid (bad length, or a non-handshake record interrupting an in-progress ClientHello reassembly).

MalformedHandshake

The known-complete ClientHello body fails ANY of the following (parser.rs’s single catch-all for the inner body, since none of them can be NeedMore once the outer handshake framing has already proven the body fully present):

• the handshake message is not a ClientHello (wrong msg_type);
• a length-prefixed field inside the body lies about the bytes available (session_id/cipher_suites/compression_methods/ extensions-block lengths, or a nested extension’s own declared length);
• the server_name extension’s host_name is not valid UTF-8;
• a second server_name extension, or a second alpn extension, is present (RFC 8446 §4.2 forbids more than one of the same type — Sōzu forwards the original bytes verbatim, so silently resolving a duplicate differently than a tolerant backend would be a routing/ forwarding mismatch);
• a single server_name extension’s server_name_list itself carries more than one host_name (type 0) entry (RFC 6066 §3);
• the alpn extension’s protocol_name_list contains a zero-length protocol name, or is present but empty (RFC 7301 §3.1 declares both 1..2^8-1-length names and a non-empty list).

Fragmented

The preread deadline fired before a terminal verdict was reached.

TooLarge

The accumulated window reached PrereadConfig::max_bytes while the PROXY header / ClientHello was still incomplete – it can never complete within the cap. A COMPLETE hello routes regardless of total window length (post-hello trailing bytes are normal in passthrough).

NoSni

No usable SNI: the server_name extension was absent, empty, or its RFC 6066 host_name entry was missing.

EchOuterAbsent

encrypted_client_hello (0xfe0d) was present and no usable outer server_name was available – distinguished from Self::NoSni because an ECH-hiding client is a different operational signal.

SniUnmatched

The normalized SNI matched no route.

AlpnUnmatched

The SNI matched a route, but no entry’s AlpnMatcher accepted the client’s offered ALPN protocols (and no AlpnMatcher::Any entry was present either).

ProxyHeaderInvalid

The PROXY-v2 header itself failed to parse.

FrontClosed

The frontend closed before a decision was reached.

Trait Implementations

impl Clone for RejectReason

fn clone(&self) -> RejectReason

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Copy for RejectReason

impl Debug for RejectReason

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Eq for RejectReason

impl PartialEq for RejectReason

fn eq(&self, other: &RejectReason) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl StructuralPartialEq for RejectReason