X-Git-Url: http://git.euphorik.ch/?p=crypto_lab2.git;a=blobdiff_plain;f=labo2-fsharp%2FCryptoFile%2FAPI.fs;h=2f80c070fec56e6683a44bb79b55ca085ad668b1;hp=424959da80403c3b1bb88ad0fcfcfa29f687f154;hb=a29300558755d533aff12a6fb668c7e985ca4617;hpb=2fcf3ed38874e9aa6d2ccd6b9917bd3113d76aee

diff --git a/labo2-fsharp/CryptoFile/API.fs b/labo2-fsharp/CryptoFile/API.fs
index 424959d..2f80c07 100644
--- a/labo2-fsharp/CryptoFile/API.fs
+++ b/labo2-fsharp/CryptoFile/API.fs
@@ -9,7 +9,7 @@ type internal Metadata (d: (string * string) list) =
     new (stream : Stream) =
         let reader = new BinaryReader (stream)
         let length = reader.ReadByte () |> int
-        new Metadata ([for i in 1..length -> reader.ReadString (), reader.ReadString ()])
+        Metadata ([for i in 1..length -> reader.ReadString (), reader.ReadString ()])
 
     // Write metadata to a stream.
     member this.WriteTo (stream : Stream) =
@@ -24,20 +24,20 @@ type internal Metadata (d: (string * string) list) =
                     | _ -> None) d
 
 module API =
-    module internal Metadata =
-        let filenameKey = "filename"
-        let modificationTimeKey = "file-modification-time"
+    module internal MetadataKeys =
+        let filename = "filename"
+        let modificationTime = "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)
+        let keyAES, keyMAC, iv = Crypto.rand 16, Crypto.rand 32, Crypto.rand 16
+        let fileInfo = FileInfo (inputFilePath)
         use inputStream = fileInfo.OpenRead ()
-        use outputStream = new FileStream (outputFilePath, FileMode.Create, FileAccess.Write, FileShare.Read, 4096 * 100)
-        let writer = new BinaryWriter (outputStream)
+        use outputStream = new FileStream (outputFilePath, FileMode.Create, FileAccess.Write)
+        use writer = new BinaryWriter (outputStream)
 
         outputStream.Position <- 32L + 256L // Skips mac and signature. They will be written later.
 
@@ -46,11 +46,11 @@ module API =
         // Plaintext -> cryptoStream -> hmacStream -> cyphertext.
         let hmacStream, hmac = Crypto.HMACStream keyMAC outputStream
         use cryptoStream = Crypto.encryptAES keyAES iv hmacStream
-        let cryptoWriter = new BinaryWriter (cryptoStream)
+        use cryptoWriter = new BinaryWriter (cryptoStream)
 
         // Write the file metadata.
-        let metaData = new Metadata ([Metadata.filenameKey, fileInfo.Name
-                                      Metadata.modificationTimeKey, fileInfo.LastWriteTimeUtc.Ticks.ToString ()])
+        let metaData = Metadata ([MetadataKeys.filename, fileInfo.Name
+                                  MetadataKeys.modificationTime, fileInfo.LastWriteTimeUtc.Ticks.ToString ()])
         metaData.WriteTo cryptoStream
 
         // Write the content of the file.
@@ -77,9 +77,9 @@ module API =
             try reader.ReadBytes 256 |> Crypto.decryptRSA decryptPrivKey
             with 
                 | :? Security.Cryptography.CryptographicException -> raise UnableToDecryptAESKeys
-        let keyAES = keys.[0..31]
-        let keyMAC = keys.[32..63]
-        let iv = keys.[64..79]
+        let keyAES = keys.[0..15]
+        let keyMAC = keys.[16..47]
+        let iv = keys.[48..63]
 
         // Integrity validation.
         let mac' = Crypto.ComputeHMAC keyMAC inputStream
@@ -93,12 +93,12 @@ module API =
         // Decrypt metadata.
         inputStream.Position <- 32L + 256L + 256L
         use cryptoStream = Crypto.decryptAES keyAES iv inputStream
-        let metadata = new Metadata (cryptoStream)
+        let metadata = Metadata cryptoStream
 
         // Create the file and write its content and metadata.
-        let filePath = Path.Combine (targetDirPath, metadata.get Metadata.filenameKey)
-        let modificationTime = new DateTime (metadata.get Metadata.modificationTimeKey |> int64)
-        let fileInfo = new FileInfo (filePath)
+        let filePath = Path.Combine (targetDirPath, metadata.get MetadataKeys.filename)
+        let modificationTime = DateTime (metadata.get MetadataKeys.modificationTime |> int64)
+        let fileInfo = FileInfo filePath
         using (fileInfo.Create ()) <| fun outputStream -> cryptoStream.CopyTo outputStream
         fileInfo.LastWriteTimeUtc <- modificationTime
     
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