val writer_info: #k:id -> w:stream_writer k -> info
val writer_info: #k:id -> w:stream_writer k -> info
let writer_info #k w = w.info
module Model.QUIC

module HS = FStar.HyperStack
module I = Model.Indexing
module U8 = FStar.UInt8
module U32 = FStar.UInt32
module U64 = FStar.UInt64
module U128 = FStar.UInt128
module M = LowStar.Modifies

friend QUIC.TotSpec

module Spec = QUIC.Spec
module TSpec = QUIC.TotSpec
module QH = QUIC.Spec.Header
module AE = Model.AEAD
module SAE = Spec.Agile.AEAD
module PNE = Model.PNE
module SPNE = Spec.Agile.Cipher
module BF = LowParse.BitFields
module U62 = QUIC.UInt62
module Secret = QUIC.Secret.Int
module B = LowStar.Buffer

open FStar.HyperStack.ST
open FStar.UInt32
open Mem

let pne_plain (j:PNE.id) (l:pnl) : eqtype = Spec.lbytes l & PNE.length_bits l
let as_bytes (j:PNE.id) (l:pnl) (x:pne_plain j l) : GTot (Helpers.lbytes l & PNE.length_bits l) = let (n,b) = x in (Helpers.hide n, b)
let repr (j:PNE.unsafe_id) (l:pnl) (x:pne_plain j l) : b:(Helpers.lbytes l & PNE.length_bits l){b == as_bytes j l x} =
  let (n,b)=x in (Helpers.hide n, b)
let mk (j:PNE.id) (l:pnl) (n:Helpers.lbytes l) (b:PNE.length_bits l) : p:pne_plain j l{as_bytes j l p == (n,b)} = Helpers.reveal n,b

let extend (#l:pnl) (b:Spec.lbytes l) (l':pnl)
  : Spec.lbytes l' =
  if l' <= l then Seq.slice b 0 l'
  else Seq.append (Seq.create (l'-l) 0z) b

let pnenc (j:PNE.id) (l:pnl) (p:pne_plain j l) (c:PNE.pne_cipherpad)
  : (l':pnl & pne_plain j l') =
  let npn, bits = p in
  let pnm, bm = c in
  QUIC.UInt.lemma_logxor_lt #8 bits bm 5;
  let v = BF.get_bitfield #8 (bits `FStar.UInt.logxor` bm) 0 5 in
  BF.set_bitfield_bound bits 5 0 5 v;
  let bits' : PNE.bits = BF.set_bitfield bits 0 5 v in
  let ln : pnl = BF.get_bitfield bits' 0 2 + 1 in
  let npn' : Spec.lbytes ln = extend #l npn ln in    
  let npn'' = QUIC.Spec.Lemmas.xor_inplace npn' (Seq.slice (Helpers.reveal pnm) 0 ln) 0 in
  (| ln, (npn', bits') |)

let lemma_xor (j:PNE.id) (l:pnl) (p:(Spec.lbytes l & PNE.length_bits l)) (c:PNE.pne_cipherpad)
  : Lemma (requires True)
  (ensures (let (| l', b' |) = pnenc j l p c in
    let _, bits = as_bytes j l' b' in
    let l:pnl = LowParse.BitFields.get_bitfield bits 0 2 + 1 in
    l == (l' <: pnl)))
  = ()

// The (abstract) type of encrypted QUIC headers,
let pne_pkg =
  PNE.PNEPlainPkg pne_plain as_bytes repr mk pnenc lemma_xor

type _ctr (offset:pn) = p:pn{p >= offset}

noeq type stream_writer' (i:id) = 
| Writer:
  info: info ->
  offset: pn ->
  siv: Spec.lbytes 12 ->
  ae: AE.aead_writer (dfst i){(AEAD.wgetinfo ae).AEAD.min_len == 3} ->
  pne_info: PNE.info (dsnd i){
    pne_info.PNE.calg == Spec.Agile.AEAD.cipher_alg_of_supported_alg (AEAD.wgetinfo ae).AEAD.alg /\
    pne_info.PNE.halg == (AEAD.wgetinfo ae).AEAD.halg /\
    pne_info.PNE.plain == pne_pkg} ->
  pne: PNE.pne_state pne_info ->
  ctr: reference (_ctr offset) ->
  stream_writer' i

let stream_writer = stream_writer'

type _last (offset:pn) = p:nat{p >= offset /\ p < max_ctr}

noeq type stream_reader' (#i:id) (w:stream_writer i) = 
| Reader:
  aer: AE.aead_reader (w.ae) ->
  last: reference (_last w.offset) ->
  stream_reader' w

let stream_reader = stream_reader'
/
Spec.Agile.Cipher.fsti.checked Spec.Agile.AEAD.fsti.checked QUIC.UInt62.fst.checked QUIC.UInt.fst.checked QUIC.TotSpec.fst.checked QUIC.Spec.Lemmas.fst.checked QUIC.Spec.Header.Parse.fsti.checked QUIC.Spec.Header.fsti.checked QUIC.Spec.fsti.checked QUIC.Secret.Int.fsti.checked prims.fst.checked Model.PNE.fsti.checked Model.Indexing.fsti.checked Model.Helpers.fsti.checked Model.AEAD.fsti.checked Mem.fst.checked LowStar.Modifies.fst.checked LowStar.Buffer.fst.checked LowParse.BitFields.fsti.checked Lib.RawIntTypes.fsti.checked FStar.UInt8.fsti.checked FStar.UInt64.fsti.checked FStar.UInt32.fsti.checked FStar.UInt128.fsti.checked FStar.UInt.fsti.checked FStar.Seq.fst.checked FStar.Pervasives.Native.fst.checked FStar.Pervasives.fsti.checked FStar.HyperStack.ST.fsti.checked FStar.HyperStack.fst.checked FStar.Endianness.fsti.checked FStar.Classical.fsti.checked
Model.QUIC.fst
w: Model.QUIC.stream_writer k -> Model.QUIC.info
Model.QUIC.id Model.QUIC.stream_writer Model.QUIC.__proj__Writer__item__info Model.QUIC.info
let writer_info #k w =
  
w.info