labo2-fsharp/CryptoFile/API.fs

   1 namespace CryptoFile
   2 open System.IO
   3
   4 type internal Metadata (d : (string * string) list) =
   5     new (stream : Stream, size: int) =
   6         let binaryReader = new BinaryReader (stream)
   7         new Metadata ([])
   8     member this.WriteTo (stream : Stream) =
   9         let binaryWriter = new BinaryWriter (stream)
  10         List.iter (fun (key : string, value : string) -> binaryWriter.Write key; binaryWriter.Write value) d
  11
  12 module API =
  13     let internal filename = "filename"
  14     let internal creationTimeKey = "file-creation-time"
  15
  16     let generatKeysPair : Key * Key = Crypto.generateRSAKeysPair
  17
  18     let encryptFile (inputFilePath : string) (outputFilePath : string) (signaturePrivKey: Key) (cryptPubKey : Key)  =
  19         let keyAES, keyMAC, iv = Crypto.rand 32, Crypto.rand 32, Crypto.rand 16
  20         let fileInfo = new FileInfo (inputFilePath)
  21         use inputStream = new FileStream (inputFilePath, FileMode.Open, FileAccess.Read)
  22         use outputStream = new FileStream (outputFilePath, FileMode.Create, FileAccess.Write)
  23         let writer = new BinaryWriter (outputStream)
  24
  25         ignore <| writer.Seek (8 + 32 + 256, SeekOrigin.Current) // Skips file-content-size, mac and signature. They will be written later.
  26
  27         Crypto.encryptRSA cryptPubKey (Array.append keyAES <| Array.append keyMAC iv) |> writer.Write
  28
  29         printfn "pos: %A" outputStream.Position
  30
  31         use cryptoStream = Crypto.encryptAES keyAES iv outputStream
  32         let cryptoWriter = new BinaryWriter (cryptoStream)
  33
  34         // Write metadata.
  35         let metaData = new Metadata ([filename, fileInfo.Name; creationTimeKey, fileInfo.CreationTimeUtc.Ticks.ToString ()])
  36         let metaDataStream = new MemoryStream ()
  37         metaData.WriteTo metaDataStream
  38         cryptoWriter.Write (int metaDataStream.Length)
  39         printfn "meta size: %A" (int metaDataStream.Length)
  40         metaDataStream.Position <- 0L
  41         metaDataStream.CopyTo cryptoStream
  42         ()
  43
  44     let decryptFile (sourceFilePath : string) (targetDirPath : string) (signaturePubKey: Key) (decryptPrivKey : Key) =
  45         ()