Clean up.

[crypto_lab2.git] / labo2-fsharp / CryptoFile / API.fs

diff --git a/labo2-fsharp/CryptoFile/API.fs b/labo2-fsharp/CryptoFile/API.fs
index 250bdbe..80f3a3d 100644 (file)
--- a/labo2-fsharp/CryptoFile/API.fs
+++ b/labo2-fsharp/CryptoFile/API.fs
@@ -28,18 +28,20 @@ module API =
         let filenameKey = "filename"
         let modificationTimeKey = "file-modification-time"
 
+    let internal (@@) a1 a2 = Array.append a1 a2
+
     let generatKeysPair : Key * Key = Crypto.generateRSAKeysPair
 
     let encryptFile (inputFilePath : string) (outputFilePath : string) (signaturePrivKey: Key) (cryptPubKey : Key)  =
         let keyAES, keyMAC, iv = Crypto.rand 32, Crypto.rand 32, Crypto.rand 16
         let fileInfo = new FileInfo (inputFilePath)
-        use inputStream = new FileStream (inputFilePath, FileMode.Open, FileAccess.Read)
+        use inputStream = fileInfo.OpenRead ()
         use outputStream = new FileStream (outputFilePath, FileMode.Create, FileAccess.Write)
         let writer = new BinaryWriter (outputStream)
 
-        writer.Seek (32 + 256, SeekOrigin.Current) |> ignore // Skips mac and signature. They will be written later.
+        outputStream.Position <- 32L + 256L // Skips mac and signature. They will be written later.
 
-        Crypto.encryptRSA cryptPubKey (Array.append keyAES <| Array.append keyMAC iv) |> writer.Write
+        Crypto.encryptRSA cryptPubKey (keyAES @@ keyMAC @@ iv) |> writer.Write
 
         // Plaintext -> cryptoStream -> hmacStream -> cyphertext.
         let hmacStream, hmac = Crypto.HMACStream keyMAC outputStream
@@ -62,6 +64,10 @@ module API =
         // Write the signature.
         Crypto.signRSA signaturePrivKey hmac.Hash |> writer.Write
 
+    // May raise one of the following error:
+    //  * IntegrityError
+    //  * SignatureMismatch 
+    //  * UnableToDecryptAESKeys
     let decryptFile (sourceFilePath : string) (targetDirPath : string) (signaturePubKey: Key) (decryptPrivKey : Key) =
         use inputStream = new FileStream (sourceFilePath, FileMode.Open, FileAccess.Read)
         use reader = new BinaryReader (inputStream)