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use crate::builder::{ConfigBuilder, WantsCipherSuites};
use crate::common_state::{CommonState, Context, Side, State};
use crate::conn::{ConnectionCommon, ConnectionCore};
use crate::dns_name::DnsName;
use crate::enums::{CipherSuite, ProtocolVersion, SignatureScheme};
use crate::error::Error;
use crate::kx::SupportedKxGroup;
#[cfg(feature = "logging")]
use crate::log::trace;
use crate::msgs::base::Payload;
use crate::msgs::handshake::{ClientHelloPayload, ProtocolName, ServerExtension};
use crate::msgs::message::Message;
use crate::sign;
use crate::suites::SupportedCipherSuite;
use crate::vecbuf::ChunkVecBuffer;
use crate::verify;
#[cfg(feature = "secret_extraction")]
use crate::ExtractedSecrets;
use crate::KeyLog;
use super::hs;
use std::marker::PhantomData;
use std::ops::{Deref, DerefMut};
use std::sync::Arc;
use std::{fmt, io};
/// A trait for the ability to store server session data.
///
/// The keys and values are opaque.
///
/// Both the keys and values should be treated as
/// **highly sensitive data**, containing enough key material
/// to break all security of the corresponding sessions.
///
/// Implementations can be lossy (in other words, forgetting
/// key/value pairs) without any negative security consequences.
///
/// However, note that `take` **must** reliably delete a returned
/// value. If it does not, there may be security consequences.
///
/// `put` and `take` are mutating operations; this isn't expressed
/// in the type system to allow implementations freedom in
/// how to achieve interior mutability. `Mutex` is a common
/// choice.
pub trait StoresServerSessions: Send + Sync {
/// Store session secrets encoded in `value` against `key`,
/// overwrites any existing value against `key`. Returns `true`
/// if the value was stored.
fn put(&self, key: Vec<u8>, value: Vec<u8>) -> bool;
/// Find a value with the given `key`. Return it, or None
/// if it doesn't exist.
fn get(&self, key: &[u8]) -> Option<Vec<u8>>;
/// Find a value with the given `key`. Return it and delete it;
/// or None if it doesn't exist.
fn take(&self, key: &[u8]) -> Option<Vec<u8>>;
/// Whether the store can cache another session. This is used to indicate to clients
/// whether their session can be resumed; the implementation is not required to remember
/// a session even if it returns `true` here.
fn can_cache(&self) -> bool;
}
/// A trait for the ability to encrypt and decrypt tickets.
pub trait ProducesTickets: Send + Sync {
/// Returns true if this implementation will encrypt/decrypt
/// tickets. Should return false if this is a dummy
/// implementation: the server will not send the SessionTicket
/// extension and will not call the other functions.
fn enabled(&self) -> bool;
/// Returns the lifetime in seconds of tickets produced now.
/// The lifetime is provided as a hint to clients that the
/// ticket will not be useful after the given time.
///
/// This lifetime must be implemented by key rolling and
/// erasure, *not* by storing a lifetime in the ticket.
///
/// The objective is to limit damage to forward secrecy caused
/// by tickets, not just limiting their lifetime.
fn lifetime(&self) -> u32;
/// Encrypt and authenticate `plain`, returning the resulting
/// ticket. Return None if `plain` cannot be encrypted for
/// some reason: an empty ticket will be sent and the connection
/// will continue.
fn encrypt(&self, plain: &[u8]) -> Option<Vec<u8>>;
/// Decrypt `cipher`, validating its authenticity protection
/// and recovering the plaintext. `cipher` is fully attacker
/// controlled, so this decryption must be side-channel free,
/// panic-proof, and otherwise bullet-proof. If the decryption
/// fails, return None.
fn decrypt(&self, cipher: &[u8]) -> Option<Vec<u8>>;
}
/// How to choose a certificate chain and signing key for use
/// in server authentication.
pub trait ResolvesServerCert: Send + Sync {
/// Choose a certificate chain and matching key given simplified
/// ClientHello information.
///
/// Return `None` to abort the handshake.
fn resolve(&self, client_hello: ClientHello) -> Option<Arc<sign::CertifiedKey>>;
}
/// A struct representing the received Client Hello
pub struct ClientHello<'a> {
server_name: &'a Option<DnsName>,
signature_schemes: &'a [SignatureScheme],
alpn: Option<&'a Vec<ProtocolName>>,
cipher_suites: &'a [CipherSuite],
}
impl<'a> ClientHello<'a> {
/// Creates a new ClientHello
pub(super) fn new(
server_name: &'a Option<DnsName>,
signature_schemes: &'a [SignatureScheme],
alpn: Option<&'a Vec<ProtocolName>>,
cipher_suites: &'a [CipherSuite],
) -> Self {
trace!("sni {:?}", server_name);
trace!("sig schemes {:?}", signature_schemes);
trace!("alpn protocols {:?}", alpn);
trace!("cipher suites {:?}", cipher_suites);
ClientHello {
server_name,
signature_schemes,
alpn,
cipher_suites,
}
}
/// Get the server name indicator.
///
/// Returns `None` if the client did not supply a SNI.
pub fn server_name(&self) -> Option<&str> {
self.server_name
.as_ref()
.map(<DnsName as AsRef<str>>::as_ref)
}
/// Get the compatible signature schemes.
///
/// Returns standard-specified default if the client omitted this extension.
pub fn signature_schemes(&self) -> &[SignatureScheme] {
self.signature_schemes
}
/// Get the ALPN protocol identifiers submitted by the client.
///
/// Returns `None` if the client did not include an ALPN extension.
///
/// Application Layer Protocol Negotiation (ALPN) is a TLS extension that lets a client
/// submit a set of identifiers that each a represent an application-layer protocol.
/// The server will then pick its preferred protocol from the set submitted by the client.
/// Each identifier is represented as a byte array, although common values are often ASCII-encoded.
/// See the official RFC-7301 specifications at <https://datatracker.ietf.org/doc/html/rfc7301>
/// for more information on ALPN.
///
/// For example, a HTTP client might specify "http/1.1" and/or "h2". Other well-known values
/// are listed in the at IANA registry at
/// <https://www.iana.org/assignments/tls-extensiontype-values/tls-extensiontype-values.xhtml#alpn-protocol-ids>.
///
/// The server can specify supported ALPN protocols by setting [`ServerConfig::alpn_protocols`].
/// During the handshake, the server will select the first protocol configured that the client supports.
pub fn alpn(&self) -> Option<impl Iterator<Item = &'a [u8]>> {
self.alpn.map(|protocols| {
protocols
.iter()
.map(|proto| proto.as_ref())
})
}
/// Get cipher suites.
pub fn cipher_suites(&self) -> &[CipherSuite] {
self.cipher_suites
}
}
/// Common configuration for a set of server sessions.
///
/// Making one of these can be expensive, and should be
/// once per process rather than once per connection.
///
/// These must be created via the [`ServerConfig::builder()`] function.
///
/// # Defaults
///
/// * [`ServerConfig::max_fragment_size`]: the default is `None`: TLS packets are not fragmented to a specific size.
/// * [`ServerConfig::session_storage`]: the default stores 256 sessions in memory.
/// * [`ServerConfig::alpn_protocols`]: the default is empty -- no ALPN protocol is negotiated.
/// * [`ServerConfig::key_log`]: key material is not logged.
/// * [`ServerConfig::send_tls13_tickets`]: 4 tickets are sent.
#[derive(Clone)]
pub struct ServerConfig {
/// List of ciphersuites, in preference order.
pub(super) cipher_suites: Vec<SupportedCipherSuite>,
/// List of supported key exchange groups.
///
/// The first is the highest priority: they will be
/// offered to the client in this order.
pub(super) kx_groups: Vec<&'static SupportedKxGroup>,
/// Ignore the client's ciphersuite order. Instead,
/// choose the top ciphersuite in the server list
/// which is supported by the client.
pub ignore_client_order: bool,
/// The maximum size of TLS message we'll emit. If None, we don't limit TLS
/// message lengths except to the 2**16 limit specified in the standard.
///
/// rustls enforces an arbitrary minimum of 32 bytes for this field.
/// Out of range values are reported as errors from ServerConnection::new.
///
/// Setting this value to the TCP MSS may improve latency for stream-y workloads.
pub max_fragment_size: Option<usize>,
/// How to store client sessions.
pub session_storage: Arc<dyn StoresServerSessions + Send + Sync>,
/// How to produce tickets.
pub ticketer: Arc<dyn ProducesTickets>,
/// How to choose a server cert and key.
pub cert_resolver: Arc<dyn ResolvesServerCert>,
/// Protocol names we support, most preferred first.
/// If empty we don't do ALPN at all.
pub alpn_protocols: Vec<Vec<u8>>,
/// Supported protocol versions, in no particular order.
/// The default is all supported versions.
pub(super) versions: crate::versions::EnabledVersions,
/// How to verify client certificates.
pub(super) verifier: Arc<dyn verify::ClientCertVerifier>,
/// How to output key material for debugging. The default
/// does nothing.
pub key_log: Arc<dyn KeyLog>,
/// Allows traffic secrets to be extracted after the handshake,
/// e.g. for kTLS setup.
#[cfg(feature = "secret_extraction")]
#[cfg_attr(docsrs, doc(cfg(feature = "secret_extraction")))]
pub enable_secret_extraction: bool,
/// Amount of early data to accept for sessions created by
/// this config. Specify 0 to disable early data. The
/// default is 0.
///
/// Read the early data via [`ServerConnection::early_data`].
///
/// The units for this are _both_ plaintext bytes, _and_ ciphertext
/// bytes, depending on whether the server accepts a client's early_data
/// or not. It is therefore recommended to include some slop in
/// this value to account for the unknown amount of ciphertext
/// expansion in the latter case.
pub max_early_data_size: u32,
/// Whether the server should send "0.5RTT" data. This means the server
/// sends data after its first flight of handshake messages, without
/// waiting for the client to complete the handshake.
///
/// This can improve TTFB latency for either server-speaks-first protocols,
/// or client-speaks-first protocols when paired with "0RTT" data. This
/// comes at the cost of a subtle weakening of the normal handshake
/// integrity guarantees that TLS provides. Note that the initial
/// `ClientHello` is indirectly authenticated because it is included
/// in the transcript used to derive the keys used to encrypt the data.
///
/// This only applies to TLS1.3 connections. TLS1.2 connections cannot
/// do this optimisation and this setting is ignored for them. It is
/// also ignored for TLS1.3 connections that even attempt client
/// authentication.
///
/// This defaults to false. This means the first application data
/// sent by the server comes after receiving and validating the client's
/// handshake up to the `Finished` message. This is the safest option.
pub send_half_rtt_data: bool,
/// How many TLS1.3 tickets to send immediately after a successful
/// handshake.
///
/// Because TLS1.3 tickets are single-use, this allows
/// a client to perform multiple resumptions.
///
/// The default is 4.
///
/// If this is 0, no tickets are sent and clients will not be able to
/// do any resumption.
pub send_tls13_tickets: usize,
}
impl fmt::Debug for ServerConfig {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
f.debug_struct("ServerConfig")
.field("ignore_client_order", &self.ignore_client_order)
.field("max_fragment_size", &self.max_fragment_size)
.field("alpn_protocols", &self.alpn_protocols)
.field("max_early_data_size", &self.max_early_data_size)
.field("send_half_rtt_data", &self.send_half_rtt_data)
.field("send_tls13_tickets", &self.send_tls13_tickets)
.finish_non_exhaustive()
}
}
impl ServerConfig {
/// Create builder to build up the server configuration.
///
/// For more information, see the [`ConfigBuilder`] documentation.
pub fn builder() -> ConfigBuilder<Self, WantsCipherSuites> {
ConfigBuilder {
state: WantsCipherSuites(()),
side: PhantomData,
}
}
/// We support a given TLS version if it's quoted in the configured
/// versions *and* at least one ciphersuite for this version is
/// also configured.
pub(crate) fn supports_version(&self, v: ProtocolVersion) -> bool {
self.versions.contains(v)
&& self
.cipher_suites
.iter()
.any(|cs| cs.version().version == v)
}
}
/// Allows reading of early data in resumed TLS1.3 connections.
///
/// "Early data" is also known as "0-RTT data".
///
/// This structure implements [`std::io::Read`].
pub struct ReadEarlyData<'a> {
early_data: &'a mut EarlyDataState,
}
impl<'a> ReadEarlyData<'a> {
fn new(early_data: &'a mut EarlyDataState) -> Self {
ReadEarlyData { early_data }
}
}
impl<'a> std::io::Read for ReadEarlyData<'a> {
fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> {
self.early_data.read(buf)
}
#[cfg(read_buf)]
fn read_buf(&mut self, cursor: io::BorrowedCursor<'_>) -> io::Result<()> {
self.early_data.read_buf(cursor)
}
}
/// This represents a single TLS server connection.
///
/// Send TLS-protected data to the peer using the `io::Write` trait implementation.
/// Read data from the peer using the `io::Read` trait implementation.
pub struct ServerConnection {
inner: ConnectionCommon<ServerConnectionData>,
}
impl ServerConnection {
/// Make a new ServerConnection. `config` controls how
/// we behave in the TLS protocol.
pub fn new(config: Arc<ServerConfig>) -> Result<Self, Error> {
Ok(Self {
inner: ConnectionCommon::from(ConnectionCore::for_server(config, Vec::new())?),
})
}
/// Retrieves the server name, if any, used to select the certificate and
/// private key.
///
/// This returns `None` until some time after the client's server name indication
/// (SNI) extension value is processed during the handshake. It will never be
/// `None` when the connection is ready to send or process application data,
/// unless the client does not support SNI.
///
/// This is useful for application protocols that need to enforce that the
/// server name matches an application layer protocol hostname. For
/// example, HTTP/1.1 servers commonly expect the `Host:` header field of
/// every request on a connection to match the hostname in the SNI extension
/// when the client provides the SNI extension.
///
/// The server name is also used to match sessions during session resumption.
pub fn server_name(&self) -> Option<&str> {
self.inner.core.get_sni_str()
}
/// Application-controlled portion of the resumption ticket supplied by the client, if any.
///
/// Recovered from the prior session's `set_resumption_data`. Integrity is guaranteed by rustls.
///
/// Returns `Some` iff a valid resumption ticket has been received from the client.
pub fn received_resumption_data(&self) -> Option<&[u8]> {
self.inner
.core
.data
.received_resumption_data
.as_ref()
.map(|x| &x[..])
}
/// Set the resumption data to embed in future resumption tickets supplied to the client.
///
/// Defaults to the empty byte string. Must be less than 2^15 bytes to allow room for other
/// data. Should be called while `is_handshaking` returns true to ensure all transmitted
/// resumption tickets are affected.
///
/// Integrity will be assured by rustls, but the data will be visible to the client. If secrecy
/// from the client is desired, encrypt the data separately.
pub fn set_resumption_data(&mut self, data: &[u8]) {
assert!(data.len() < 2usize.pow(15));
self.inner.core.data.resumption_data = data.into();
}
/// Explicitly discard early data, notifying the client
///
/// Useful if invariants encoded in `received_resumption_data()` cannot be respected.
///
/// Must be called while `is_handshaking` is true.
pub fn reject_early_data(&mut self) {
self.inner.core.reject_early_data()
}
/// Returns an `io::Read` implementer you can read bytes from that are
/// received from a client as TLS1.3 0RTT/"early" data, during the handshake.
///
/// This returns `None` in many circumstances, such as :
///
/// - Early data is disabled if [`ServerConfig::max_early_data_size`] is zero (the default).
/// - The session negotiated with the client is not TLS1.3.
/// - The client just doesn't support early data.
/// - The connection doesn't resume an existing session.
/// - The client hasn't sent a full ClientHello yet.
pub fn early_data(&mut self) -> Option<ReadEarlyData> {
let data = &mut self.inner.core.data;
if data.early_data.was_accepted() {
Some(ReadEarlyData::new(&mut data.early_data))
} else {
None
}
}
/// Extract secrets, so they can be used when configuring kTLS, for example.
#[cfg(feature = "secret_extraction")]
#[cfg_attr(docsrs, doc(cfg(feature = "secret_extraction")))]
pub fn extract_secrets(self) -> Result<ExtractedSecrets, Error> {
self.inner.extract_secrets()
}
}
impl fmt::Debug for ServerConnection {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
f.debug_struct("ServerConnection")
.finish()
}
}
impl Deref for ServerConnection {
type Target = ConnectionCommon<ServerConnectionData>;
fn deref(&self) -> &Self::Target {
&self.inner
}
}
impl DerefMut for ServerConnection {
fn deref_mut(&mut self) -> &mut Self::Target {
&mut self.inner
}
}
impl From<ServerConnection> for crate::Connection {
fn from(conn: ServerConnection) -> Self {
Self::Server(conn)
}
}
/// Handle on a server-side connection before configuration is available.
///
/// `Acceptor` allows the caller to choose a [`ServerConfig`] after reading
/// the [`ClientHello`] of an incoming connection. This is useful for servers
/// that choose different certificates or cipher suites based on the
/// characteristics of the `ClientHello`. In particular it is useful for
/// servers that need to do some I/O to load a certificate and its private key
/// and don't want to use the blocking interface provided by
/// [`ResolvesServerCert`].
///
/// Create an Acceptor with [`Acceptor::default()`].
///
/// # Example
///
/// ```no_run
/// # fn choose_server_config(
/// # _: rustls::server::ClientHello,
/// # ) -> std::sync::Arc<rustls::ServerConfig> {
/// # unimplemented!();
/// # }
/// # #[allow(unused_variables)]
/// # fn main() {
/// use rustls::server::{Acceptor, ServerConfig};
/// let listener = std::net::TcpListener::bind("127.0.0.1:0").unwrap();
/// for stream in listener.incoming() {
/// let mut stream = stream.unwrap();
/// let mut acceptor = Acceptor::default();
/// let accepted = loop {
/// acceptor.read_tls(&mut stream).unwrap();
/// if let Some(accepted) = acceptor.accept().unwrap() {
/// break accepted;
/// }
/// };
///
/// // For some user-defined choose_server_config:
/// let config = choose_server_config(accepted.client_hello());
/// let conn = accepted
/// .into_connection(config)
/// .unwrap();
/// // Proceed with handling the ServerConnection.
/// }
/// # }
//// ```
pub struct Acceptor {
inner: Option<ConnectionCommon<ServerConnectionData>>,
}
impl Default for Acceptor {
/// Return an empty Acceptor, ready to receive bytes from a new client connection.
fn default() -> Self {
Self {
inner: Some(
ConnectionCore::new(
Box::new(Accepting),
ServerConnectionData::default(),
CommonState::new(Side::Server),
)
.into(),
),
}
}
}
impl Acceptor {
/// Read TLS content from `rd`.
///
/// Returns an error if this `Acceptor` has already yielded an [`Accepted`]. For more details,
/// refer to [`Connection::read_tls()`].
///
/// [`Connection::read_tls()`]: crate::Connection::read_tls
pub fn read_tls(&mut self, rd: &mut dyn io::Read) -> Result<usize, io::Error> {
match &mut self.inner {
Some(conn) => conn.read_tls(rd),
None => Err(io::Error::new(
io::ErrorKind::Other,
"acceptor cannot read after successful acceptance",
)),
}
}
/// Check if a `ClientHello` message has been received.
///
/// Returns `Ok(None)` if the complete `ClientHello` has not yet been received.
/// Do more I/O and then call this function again.
///
/// Returns `Ok(Some(accepted))` if the connection has been accepted. Call
/// `accepted.into_connection()` to continue. Do not call this function again.
///
/// Returns `Err(err)` if an error occurred. Do not call this function again.
pub fn accept(&mut self) -> Result<Option<Accepted>, Error> {
let mut connection = match self.inner.take() {
Some(conn) => conn,
None => {
return Err(Error::General("Acceptor polled after completion".into()));
}
};
let message = match connection.first_handshake_message()? {
Some(msg) => msg,
None => {
self.inner = Some(connection);
return Ok(None);
}
};
let (_, sig_schemes) =
hs::process_client_hello(&message, false, &mut Context::from(&mut connection))?;
Ok(Some(Accepted {
connection,
message,
sig_schemes,
}))
}
}
/// Represents a `ClientHello` message received through the [`Acceptor`].
///
/// Contains the state required to resume the connection through [`Accepted::into_connection()`].
pub struct Accepted {
connection: ConnectionCommon<ServerConnectionData>,
message: Message,
sig_schemes: Vec<SignatureScheme>,
}
impl Accepted {
/// Get the [`ClientHello`] for this connection.
pub fn client_hello(&self) -> ClientHello<'_> {
let payload = Self::client_hello_payload(&self.message);
ClientHello::new(
&self.connection.core.data.sni,
&self.sig_schemes,
payload.get_alpn_extension(),
&payload.cipher_suites,
)
}
/// Convert the [`Accepted`] into a [`ServerConnection`].
///
/// Takes the state returned from [`Acceptor::accept()`] as well as the [`ServerConfig`] and
/// [`sign::CertifiedKey`] that should be used for the session. Returns an error if
/// configuration-dependent validation of the received `ClientHello` message fails.
pub fn into_connection(mut self, config: Arc<ServerConfig>) -> Result<ServerConnection, Error> {
self.connection
.set_max_fragment_size(config.max_fragment_size)?;
#[cfg(feature = "secret_extraction")]
{
self.connection.enable_secret_extraction = config.enable_secret_extraction;
}
let state = hs::ExpectClientHello::new(config, Vec::new());
let mut cx = hs::ServerContext::from(&mut self.connection);
let new = state.with_certified_key(
self.sig_schemes,
Self::client_hello_payload(&self.message),
&self.message,
&mut cx,
)?;
self.connection.replace_state(new);
Ok(ServerConnection {
inner: self.connection,
})
}
fn client_hello_payload(message: &Message) -> &ClientHelloPayload {
match &message.payload {
crate::msgs::message::MessagePayload::Handshake { parsed, .. } => match &parsed.payload
{
crate::msgs::handshake::HandshakePayload::ClientHello(ch) => ch,
_ => unreachable!(),
},
_ => unreachable!(),
}
}
}
struct Accepting;
impl State<ServerConnectionData> for Accepting {
fn handle(
self: Box<Self>,
_cx: &mut hs::ServerContext<'_>,
_m: Message,
) -> Result<Box<dyn State<ServerConnectionData>>, Error> {
Err(Error::General("unreachable state".into()))
}
}
pub(super) enum EarlyDataState {
New,
Accepted(ChunkVecBuffer),
Rejected,
}
impl Default for EarlyDataState {
fn default() -> Self {
Self::New
}
}
impl EarlyDataState {
pub(super) fn reject(&mut self) {
*self = Self::Rejected;
}
pub(super) fn accept(&mut self, max_size: usize) {
*self = Self::Accepted(ChunkVecBuffer::new(Some(max_size)));
}
fn was_accepted(&self) -> bool {
matches!(self, Self::Accepted(_))
}
pub(super) fn was_rejected(&self) -> bool {
matches!(self, Self::Rejected)
}
fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> {
match self {
Self::Accepted(ref mut received) => received.read(buf),
_ => Err(io::Error::from(io::ErrorKind::BrokenPipe)),
}
}
#[cfg(read_buf)]
fn read_buf(&mut self, cursor: io::BorrowedCursor<'_>) -> io::Result<()> {
match self {
Self::Accepted(ref mut received) => received.read_buf(cursor),
_ => Err(io::Error::from(io::ErrorKind::BrokenPipe)),
}
}
pub(super) fn take_received_plaintext(&mut self, bytes: Payload) -> bool {
let available = bytes.0.len();
match self {
Self::Accepted(ref mut received) if received.apply_limit(available) == available => {
received.append(bytes.0);
true
}
_ => false,
}
}
}
// these branches not reachable externally, unless something else goes wrong.
#[test]
fn test_read_in_new_state() {
assert_eq!(
format!("{:?}", EarlyDataState::default().read(&mut [0u8; 5])),
"Err(Kind(BrokenPipe))"
);
}
#[cfg(read_buf)]
#[test]
fn test_read_buf_in_new_state() {
use std::io::BorrowedBuf;
let mut buf = [0u8; 5];
let mut buf: BorrowedBuf<'_> = buf.as_mut_slice().into();
assert_eq!(
format!("{:?}", EarlyDataState::default().read_buf(buf.unfilled())),
"Err(Kind(BrokenPipe))"
);
}
impl ConnectionCore<ServerConnectionData> {
pub(crate) fn for_server(
config: Arc<ServerConfig>,
extra_exts: Vec<ServerExtension>,
) -> Result<Self, Error> {
let mut common = CommonState::new(Side::Server);
common.set_max_fragment_size(config.max_fragment_size)?;
#[cfg(feature = "secret_extraction")]
{
common.enable_secret_extraction = config.enable_secret_extraction;
}
Ok(Self::new(
Box::new(hs::ExpectClientHello::new(config, extra_exts)),
ServerConnectionData::default(),
common,
))
}
pub(crate) fn reject_early_data(&mut self) {
assert!(
self.common_state.is_handshaking(),
"cannot retroactively reject early data"
);
self.data.early_data.reject();
}
pub(crate) fn get_sni_str(&self) -> Option<&str> {
self.data.get_sni_str()
}
}
/// State associated with a server connection.
#[derive(Default)]
pub struct ServerConnectionData {
pub(super) sni: Option<DnsName>,
pub(super) received_resumption_data: Option<Vec<u8>>,
pub(super) resumption_data: Vec<u8>,
pub(super) early_data: EarlyDataState,
}
impl ServerConnectionData {
pub(super) fn get_sni_str(&self) -> Option<&str> {
self.sni.as_ref().map(AsRef::as_ref)
}
}
impl crate::conn::SideData for ServerConnectionData {}