use crate::cipher;
use crate::error::TLSError;
use crate::key;
#[cfg(feature = "logging")]
use crate::log::{debug, error, warn};
use crate::msgs::base::Payload;
use crate::msgs::codec::Codec;
use crate::msgs::deframer::MessageDeframer;
use crate::msgs::enums::{AlertDescription, AlertLevel, ContentType, ProtocolVersion};
use crate::msgs::fragmenter::{MessageFragmenter, MAX_FRAGMENT_LEN};
use crate::msgs::hsjoiner::HandshakeJoiner;
use crate::msgs::message::{BorrowMessage, Message, MessagePayload};
use crate::prf;
use crate::quic;
use crate::rand;
use crate::record_layer;
use crate::suites::SupportedCipherSuite;
use crate::vecbuf::ChunkVecBuffer;
use ring;
use std::io::{Read, Write};
use std::collections::VecDeque;
use std::io;
pub trait Session: quic::QuicExt + Read + Write + Send + Sync {
    
    
    
    
    
    
    
    
    
    
    
    
    
    fn read_tls(&mut self, rd: &mut dyn Read) -> Result<usize, io::Error>;
    
    
    
    
    
    
    
    
    
    
    
    fn write_tls(&mut self, wr: &mut dyn Write) -> Result<usize, io::Error>;
    
    
    
    
    
    
    
    fn process_new_packets(&mut self) -> Result<(), TLSError>;
    
    
    fn wants_read(&self) -> bool;
    
    
    fn wants_write(&self) -> bool;
    
    
    
    fn is_handshaking(&self) -> bool;
    
    
    
    
    
    
    fn set_buffer_limit(&mut self, limit: usize);
    
    
    
    fn send_close_notify(&mut self);
    
    
    
    
    
    
    
    
    
    
    
    
    
    fn get_peer_certificates(&self) -> Option<Vec<key::Certificate>>;
    
    
    
    
    
    fn get_alpn_protocol(&self) -> Option<&[u8]>;
    
    
    
    fn get_protocol_version(&self) -> Option<ProtocolVersion>;
    
    
    
    
    
    
    
    
    
    
    
    
    
    fn export_keying_material(
        &self,
        output: &mut [u8],
        label: &[u8],
        context: Option<&[u8]>,
    ) -> Result<(), TLSError>;
    
    
    
    fn get_negotiated_ciphersuite(&self) -> Option<&'static SupportedCipherSuite>;
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    fn complete_io<T>(&mut self, io: &mut T) -> Result<(usize, usize), io::Error>
    where
        Self: Sized,
        T: Read + Write,
    {
        let until_handshaked = self.is_handshaking();
        let mut eof = false;
        let mut wrlen = 0;
        let mut rdlen = 0;
        loop {
            while self.wants_write() {
                wrlen += self.write_tls(io)?;
            }
            if !until_handshaked && wrlen > 0 {
                return Ok((rdlen, wrlen));
            }
            if !eof && self.wants_read() {
                match self.read_tls(io)? {
                    0 => eof = true,
                    n => rdlen += n,
                }
            }
            match self.process_new_packets() {
                Ok(_) => {}
                Err(e) => {
                    
                    
                    
                    let _ignored = self.write_tls(io);
                    return Err(io::Error::new(io::ErrorKind::InvalidData, e));
                }
            };
            match (eof, until_handshaked, self.is_handshaking()) {
                (_, true, false) => return Ok((rdlen, wrlen)),
                (_, false, _) => return Ok((rdlen, wrlen)),
                (true, true, true) => return Err(io::Error::from(io::ErrorKind::UnexpectedEof)),
                (..) => {}
            }
        }
    }
}
#[derive(Copy, Clone, Eq, PartialEq)]
pub enum Protocol {
    Tls13,
    #[cfg(feature = "quic")]
    Quic,
}
#[derive(Clone, Debug)]
pub struct SessionRandoms {
    pub we_are_client: bool,
    pub client: [u8; 32],
    pub server: [u8; 32],
}
static TLS12_DOWNGRADE_SENTINEL: &[u8] = &[0x44, 0x4f, 0x57, 0x4e, 0x47, 0x52, 0x44, 0x01];
impl SessionRandoms {
    pub fn for_server() -> SessionRandoms {
        let mut ret = SessionRandoms {
            we_are_client: false,
            client: [0u8; 32],
            server: [0u8; 32],
        };
        rand::fill_random(&mut ret.server);
        ret
    }
    pub fn for_client() -> SessionRandoms {
        let mut ret = SessionRandoms {
            we_are_client: true,
            client: [0u8; 32],
            server: [0u8; 32],
        };
        rand::fill_random(&mut ret.client);
        ret
    }
    pub fn set_tls12_downgrade_marker(&mut self) {
        assert!(!self.we_are_client);
        self.server[24..]
            .as_mut()
            .write_all(TLS12_DOWNGRADE_SENTINEL)
            .unwrap();
    }
    pub fn has_tls12_downgrade_marker(&mut self) -> bool {
        assert!(self.we_are_client);
        
        
        &self.server[24..] == TLS12_DOWNGRADE_SENTINEL
    }
}
fn join_randoms(first: &[u8], second: &[u8]) -> [u8; 64] {
    let mut randoms = [0u8; 64];
    randoms
        .as_mut()
        .write_all(first)
        .unwrap();
    randoms[32..]
        .as_mut()
        .write_all(second)
        .unwrap();
    randoms
}
pub struct SessionSecrets {
    pub randoms: SessionRandoms,
    hash: &'static ring::digest::Algorithm,
    pub master_secret: [u8; 48],
}
impl SessionSecrets {
    pub fn new(
        randoms: &SessionRandoms,
        hashalg: &'static ring::digest::Algorithm,
        pms: &[u8],
    ) -> SessionSecrets {
        let mut ret = SessionSecrets {
            randoms: randoms.clone(),
            hash: hashalg,
            master_secret: [0u8; 48],
        };
        let randoms = join_randoms(&ret.randoms.client, &ret.randoms.server);
        prf::prf(
            &mut ret.master_secret,
            ret.hash,
            pms,
            b"master secret",
            &randoms,
        );
        ret
    }
    pub fn new_ems(
        randoms: &SessionRandoms,
        hs_hash: &[u8],
        hashalg: &'static ring::digest::Algorithm,
        pms: &[u8],
    ) -> SessionSecrets {
        let mut ret = SessionSecrets {
            randoms: randoms.clone(),
            hash: hashalg,
            master_secret: [0u8; 48],
        };
        prf::prf(
            &mut ret.master_secret,
            ret.hash,
            pms,
            b"extended master secret",
            hs_hash,
        );
        ret
    }
    pub fn new_resume(
        randoms: &SessionRandoms,
        hashalg: &'static ring::digest::Algorithm,
        master_secret: &[u8],
    ) -> SessionSecrets {
        let mut ret = SessionSecrets {
            randoms: randoms.clone(),
            hash: hashalg,
            master_secret: [0u8; 48],
        };
        ret.master_secret
            .as_mut()
            .write_all(master_secret)
            .unwrap();
        ret
    }
    pub fn make_key_block(&self, len: usize) -> Vec<u8> {
        let mut out = Vec::new();
        out.resize(len, 0u8);
        
        
        let randoms = join_randoms(&self.randoms.server, &self.randoms.client);
        prf::prf(
            &mut out,
            self.hash,
            &self.master_secret,
            b"key expansion",
            &randoms,
        );
        out
    }
    pub fn get_master_secret(&self) -> Vec<u8> {
        let mut ret = Vec::new();
        ret.extend_from_slice(&self.master_secret);
        ret
    }
    pub fn make_verify_data(&self, handshake_hash: &[u8], label: &[u8]) -> Vec<u8> {
        let mut out = Vec::new();
        out.resize(12, 0u8);
        prf::prf(
            &mut out,
            self.hash,
            &self.master_secret,
            label,
            handshake_hash,
        );
        out
    }
    pub fn client_verify_data(&self, handshake_hash: &[u8]) -> Vec<u8> {
        self.make_verify_data(handshake_hash, b"client finished")
    }
    pub fn server_verify_data(&self, handshake_hash: &[u8]) -> Vec<u8> {
        self.make_verify_data(handshake_hash, b"server finished")
    }
    pub fn export_keying_material(&self, output: &mut [u8], label: &[u8], context: Option<&[u8]>) {
        let mut randoms = Vec::new();
        randoms.extend_from_slice(&self.randoms.client);
        randoms.extend_from_slice(&self.randoms.server);
        if let Some(context) = context {
            assert!(context.len() <= 0xffff);
            (context.len() as u16).encode(&mut randoms);
            randoms.extend_from_slice(context);
        }
        prf::prf(output, self.hash, &self.master_secret, label, &randoms)
    }
}
enum Limit {
    Yes,
    No,
}
pub enum MiddleboxCCS {
    
    Process,
    
    Drop,
}
pub struct SessionCommon {
    pub negotiated_version: Option<ProtocolVersion>,
    pub is_client: bool,
    pub record_layer: record_layer::RecordLayer,
    suite: Option<&'static SupportedCipherSuite>,
    peer_eof: bool,
    pub traffic: bool,
    pub early_traffic: bool,
    sent_fatal_alert: bool,
    received_middlebox_ccs: bool,
    pub message_deframer: MessageDeframer,
    pub handshake_joiner: HandshakeJoiner,
    pub message_fragmenter: MessageFragmenter,
    received_plaintext: ChunkVecBuffer,
    sendable_plaintext: ChunkVecBuffer,
    pub sendable_tls: ChunkVecBuffer,
    
    pub protocol: Protocol,
    #[cfg(feature = "quic")]
    pub(crate) quic: Quic,
}
impl SessionCommon {
    pub fn new(mtu: Option<usize>, client: bool) -> SessionCommon {
        SessionCommon {
            negotiated_version: None,
            is_client: client,
            record_layer: record_layer::RecordLayer::new(),
            suite: None,
            peer_eof: false,
            traffic: false,
            early_traffic: false,
            sent_fatal_alert: false,
            received_middlebox_ccs: false,
            message_deframer: MessageDeframer::new(),
            handshake_joiner: HandshakeJoiner::new(),
            message_fragmenter: MessageFragmenter::new(mtu.unwrap_or(MAX_FRAGMENT_LEN)),
            received_plaintext: ChunkVecBuffer::new(),
            sendable_plaintext: ChunkVecBuffer::new(),
            sendable_tls: ChunkVecBuffer::new(),
            protocol: Protocol::Tls13,
            #[cfg(feature = "quic")]
            quic: Quic::new(),
        }
    }
    pub fn is_tls13(&self) -> bool {
        match self.negotiated_version {
            Some(ProtocolVersion::TLSv1_3) => true,
            _ => false,
        }
    }
    pub fn get_suite(&self) -> Option<&'static SupportedCipherSuite> {
        self.suite
    }
    pub fn get_suite_assert(&self) -> &'static SupportedCipherSuite {
        self.suite.as_ref().unwrap()
    }
    pub fn set_suite(&mut self, suite: &'static SupportedCipherSuite) -> bool {
        match self.suite {
            None => {
                self.suite = Some(suite);
                true
            }
            Some(s) if s == suite => {
                self.suite = Some(suite);
                true
            }
            _ => false,
        }
    }
    pub fn filter_tls13_ccs(&mut self, msg: &Message) -> Result<MiddleboxCCS, TLSError> {
        
        
        
        
        
        if !self.is_tls13() || !msg.is_content_type(ContentType::ChangeCipherSpec) || self.traffic {
            return Ok(MiddleboxCCS::Process);
        }
        if self.received_middlebox_ccs {
            Err(TLSError::PeerMisbehavedError(
                "illegal middlebox CCS received".into(),
            ))
        } else {
            self.received_middlebox_ccs = true;
            Ok(MiddleboxCCS::Drop)
        }
    }
    pub fn decrypt_incoming(&mut self, encr: Message) -> Result<Message, TLSError> {
        if self
            .record_layer
            .wants_close_before_decrypt()
        {
            self.send_close_notify();
        }
        let rc = self.record_layer.decrypt_incoming(encr);
        if let Err(TLSError::PeerSentOversizedRecord) = rc {
            self.send_fatal_alert(AlertDescription::RecordOverflow);
        }
        rc
    }
    pub fn has_readable_plaintext(&self) -> bool {
        !self.received_plaintext.is_empty()
    }
    pub fn set_buffer_limit(&mut self, limit: usize) {
        self.sendable_plaintext.set_limit(limit);
        self.sendable_tls.set_limit(limit);
    }
    pub fn process_alert(&mut self, msg: Message) -> Result<(), TLSError> {
        if let MessagePayload::Alert(ref alert) = msg.payload {
            
            if let AlertLevel::Unknown(_) = alert.level {
                self.send_fatal_alert(AlertDescription::IllegalParameter);
            }
            
            
            if alert.description == AlertDescription::CloseNotify {
                self.peer_eof = true;
                return Ok(());
            }
            
            
            if alert.level == AlertLevel::Warning {
                if self.is_tls13() && alert.description != AlertDescription::UserCanceled {
                    self.send_fatal_alert(AlertDescription::DecodeError);
                } else {
                    warn!("TLS alert warning received: {:#?}", msg);
                    return Ok(());
                }
            }
            error!("TLS alert received: {:#?}", msg);
            Err(TLSError::AlertReceived(alert.description))
        } else {
            Err(TLSError::CorruptMessagePayload(ContentType::Alert))
        }
    }
    
    
    pub fn send_msg_encrypt(&mut self, m: Message) {
        let mut plain_messages = VecDeque::new();
        self.message_fragmenter
            .fragment(m, &mut plain_messages);
        for m in plain_messages {
            self.send_single_fragment(m.to_borrowed());
        }
    }
    
    fn send_appdata_encrypt(&mut self, payload: &[u8], limit: Limit) -> usize {
        
        
        
        
        let len = match limit {
            Limit::Yes => self
                .sendable_tls
                .apply_limit(payload.len()),
            Limit::No => payload.len(),
        };
        let mut plain_messages = VecDeque::new();
        self.message_fragmenter.fragment_borrow(
            ContentType::ApplicationData,
            ProtocolVersion::TLSv1_2,
            &payload[..len],
            &mut plain_messages,
        );
        for m in plain_messages {
            self.send_single_fragment(m);
        }
        len
    }
    fn send_single_fragment(&mut self, m: BorrowMessage) {
        
        
        if self
            .record_layer
            .wants_close_before_encrypt()
        {
            self.send_close_notify();
        }
        
        
        if self.record_layer.encrypt_exhausted() {
            return;
        }
        let em = self.record_layer.encrypt_outgoing(m);
        self.queue_tls_message(em);
    }
    
    
    
    pub fn connection_at_eof(&self) -> bool {
        self.peer_eof && !self.message_deframer.has_pending()
    }
    
    
    
    pub fn read_tls(&mut self, rd: &mut dyn Read) -> io::Result<usize> {
        self.message_deframer.read(rd)
    }
    pub fn write_tls(&mut self, wr: &mut dyn Write) -> io::Result<usize> {
        self.sendable_tls.write_to(wr)
    }
    
    
    
    
    
    pub fn send_some_plaintext(&mut self, data: &[u8]) -> usize {
        self.send_plain(data, Limit::Yes)
    }
    pub fn send_early_plaintext(&mut self, data: &[u8]) -> usize {
        debug_assert!(self.early_traffic);
        debug_assert!(self.record_layer.is_encrypting());
        if data.is_empty() {
            
            return 0;
        }
        self.send_appdata_encrypt(data, Limit::Yes)
    }
    
    
    
    
    
    fn send_plain(&mut self, data: &[u8], limit: Limit) -> usize {
        if !self.traffic {
            
            
            let len = match limit {
                Limit::Yes => self
                    .sendable_plaintext
                    .append_limited_copy(data),
                Limit::No => self
                    .sendable_plaintext
                    .append(data.to_vec()),
            };
            return len;
        }
        debug_assert!(self.record_layer.is_encrypting());
        if data.is_empty() {
            
            return 0;
        }
        self.send_appdata_encrypt(data, limit)
    }
    pub fn start_traffic(&mut self) {
        self.traffic = true;
        self.flush_plaintext();
    }
    
    
    pub fn flush_plaintext(&mut self) {
        if !self.traffic {
            return;
        }
        while !self.sendable_plaintext.is_empty() {
            let buf = self.sendable_plaintext.take_one();
            self.send_plain(&buf, Limit::No);
        }
    }
    
    fn queue_tls_message(&mut self, m: Message) {
        self.sendable_tls
            .append(m.get_encoding());
    }
    
    pub fn send_msg(&mut self, m: Message, must_encrypt: bool) {
        #[cfg(feature = "quic")]
        {
            if let Protocol::Quic = self.protocol {
                if let MessagePayload::Alert(alert) = m.payload {
                    self.quic.alert = Some(alert.description);
                } else {
                    debug_assert!(
                        if let MessagePayload::Handshake(_) = m.payload {
                            true
                        } else {
                            false
                        },
                        "QUIC uses TLS for the cryptographic handshake only"
                    );
                    let mut bytes = Vec::new();
                    m.payload.encode(&mut bytes);
                    self.quic
                        .hs_queue
                        .push_back((must_encrypt, bytes));
                }
                return;
            }
        }
        if !must_encrypt {
            let mut to_send = VecDeque::new();
            self.message_fragmenter
                .fragment(m, &mut to_send);
            for mm in to_send {
                self.queue_tls_message(mm);
            }
        } else {
            self.send_msg_encrypt(m);
        }
    }
    pub fn take_received_plaintext(&mut self, bytes: Payload) {
        self.received_plaintext.append(bytes.0);
    }
    pub fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> {
        let len = self.received_plaintext.read(buf)?;
        if len == 0 && self.connection_at_eof() && self.received_plaintext.is_empty() {
            return Err(io::Error::new(
                io::ErrorKind::ConnectionAborted,
                "CloseNotify alert received",
            ));
        }
        Ok(len)
    }
    pub fn start_encryption_tls12(&mut self, secrets: &SessionSecrets) {
        let (dec, enc) = cipher::new_tls12(self.get_suite_assert(), secrets);
        self.record_layer
            .prepare_message_encrypter(enc);
        self.record_layer
            .prepare_message_decrypter(dec);
    }
    pub fn send_warning_alert(&mut self, desc: AlertDescription) {
        warn!("Sending warning alert {:?}", desc);
        self.send_warning_alert_no_log(desc);
    }
    pub fn send_fatal_alert(&mut self, desc: AlertDescription) {
        warn!("Sending fatal alert {:?}", desc);
        debug_assert!(!self.sent_fatal_alert);
        let m = Message::build_alert(AlertLevel::Fatal, desc);
        self.send_msg(m, self.record_layer.is_encrypting());
        self.sent_fatal_alert = true;
    }
    pub fn send_close_notify(&mut self) {
        debug!("Sending warning alert {:?}", AlertDescription::CloseNotify);
        self.send_warning_alert_no_log(AlertDescription::CloseNotify);
    }
    fn send_warning_alert_no_log(&mut self, desc: AlertDescription) {
        let m = Message::build_alert(AlertLevel::Warning, desc);
        self.send_msg(m, self.record_layer.is_encrypting());
    }
    pub fn is_quic(&self) -> bool {
        #[cfg(feature = "quic")]
        {
            self.protocol == Protocol::Quic
        }
        #[cfg(not(feature = "quic"))]
        false
    }
}
#[cfg(feature = "quic")]
pub(crate) struct Quic {
    
    pub params: Option<Vec<u8>>,
    pub alert: Option<AlertDescription>,
    pub hs_queue: VecDeque<(bool, Vec<u8>)>,
    pub early_secret: Option<ring::hkdf::Prk>,
    pub hs_secrets: Option<quic::Secrets>,
    pub traffic_secrets: Option<quic::Secrets>,
    
    pub returned_traffic_keys: bool,
}
#[cfg(feature = "quic")]
impl Quic {
    pub fn new() -> Self {
        Self {
            params: None,
            alert: None,
            hs_queue: VecDeque::new(),
            early_secret: None,
            hs_secrets: None,
            traffic_secrets: None,
            returned_traffic_keys: false,
        }
    }
}