improve upload

rewrite download

Crypt.go

@@ -72,9 +72,11 @@ func IsValidCipher(c string) bool {
 	return false
 }
 
-// Encrypt encrypts input stream and writes it to out
-func Encrypt(in io.Reader, out io.Writer, keyAes, buff []byte) (err error) {
+// EncryptAES encrypts input stream and writes it to out
+func EncryptAES(in io.Reader, out io.Writer, keyAes, buff []byte) (err error) {
 	iv := make([]byte, 16)
+
+	// Create random iv
 	_, err = rand.Read(iv)
 	if err != nil {
 		return err
@@ -86,8 +88,12 @@ func Encrypt(in io.Reader, out io.Writer, keyAes, buff []byte) (err error) {
 	}
 
 	ctr := cipher.NewCTR(aes, iv)
+
+	// First 16 bytes of ciphertext will
+	// be the iv, so write it!
 	out.Write(iv)
 
+	// Encrypt file
 	for {
 		n, err := in.Read(buff)
 		if err != nil && err != io.EOF {
@@ -108,27 +114,38 @@ func Encrypt(in io.Reader, out io.Writer, keyAes, buff []byte) (err error) {
 	return nil
 }
 
-// Decrypt decrypt stuff
-func Decrypt(in io.Reader, out, hashwriter io.Writer, keyAes, buff []byte) (err error) {
+// DecryptAES decrypt stuff
+func DecryptAES(in io.Reader, out, hashwriter io.Writer, keyAes, buff []byte, cancenChan chan bool) (err error) {
+	// Iv is always 16 bytes
 	iv := make([]byte, 16)
 
 	aes, err := aes.NewCipher(keyAes)
 	if err != nil {
 		return err
 	}
 
+	// Read first 16 bytes to iv
 	n, err := in.Read(iv)
 	if err != nil {
 		return err
 	}
 
+	// If not 16 bytes were written, there
+	// is a big problem
 	if n != 16 {
 		return errors.New("reading aes iv")
 	}
 
+	// Write iv to hasher cause the servers
+	// hash is built on it too
 	hashwriter.Write(iv)
 	ctr := cipher.NewCTR(aes, iv)
 
+	// Decrypt using xor keystream the
+	// cipher input text is written to the
+	// hashwriter since the servers has no
+	// key and built it's hash using the
+	// encrypted text
 	for {
 		n, err := in.Read(buff)
 		if err != nil && err != io.EOF {
@@ -138,10 +155,13 @@ func Decrypt(in io.Reader, out, hashwriter io.Writer, keyAes, buff []byte) (err
 		if n != 0 {
 			outBuf := make([]byte, n)
 			ctr.XORKeyStream(outBuf, buff[:n])
+
 			out.Write(outBuf)
 			hashwriter.Write(buff[:n])
 		}
 
+		// Treat eof as stop condition, not as
+		// an error
 		if err == io.EOF {
 			break
 		}

File.go

@@ -1,16 +1,10 @@
 package libdatamanager
 
 import (
-	"encoding/hex"
-	"hash/crc32"
 	"io"
 	"net/http"
-	"os"
-	"path/filepath"
 	"strconv"
 	"time"
-
-	"github.com/pkg/errors"
 )
 
 // FileAttributes attributes for a file
@@ -53,6 +47,17 @@ type FileChanges struct {
 	SetPublic, SetPrivate    bool
 }
 
+const (
+	// DefaultBuffersize The default buffersize for filestreams
+	DefaultBuffersize = 10 * 1024
+)
+
+// WriterProxy proxy writing
+type WriterProxy func(io.Writer) io.Writer
+
+// FileSizeCallback gets called if the filesize is known
+type FileSizeCallback func(int64)
+
 // DeleteFile deletes the desired file(s)
 func (libdm LibDM) DeleteFile(name string, id uint, all bool, attributes FileAttributes) (*IDsResponse, error) {
 	var response IDsResponse
@@ -119,98 +124,6 @@ func (libdm LibDM) PublishFile(name string, id uint, publicName string, all bool
 	return resp, nil
 }
 
-// GetFile requests a filedownload and returns the response
-// -> response, serverfilename, checksum, error
-// The response body must be closed
-func (libdm LibDM) GetFile(name string, id uint, namespace string) (*http.Response, string, string, error) {
-	resp, err := libdm.NewRequest(EPFileGet, &FileRequest{
-		Name:   name,
-		FileID: id,
-		Attributes: FileAttributes{
-			Namespace: namespace,
-		},
-	}).WithAuthFromConfig().DoHTTPRequest()
-
-	// Check for error
-	if err != nil {
-		return nil, "", "", &ResponseErr{
-			Err: err,
-		}
-	}
-
-	// Check response headers
-	if resp.Header.Get(HeaderStatus) == strconv.Itoa(int(ResponseError)) {
-		return nil, "", "", &ResponseErr{
-			Response: &RestRequestResponse{
-				HTTPCode: resp.StatusCode,
-				Headers:  &resp.Header,
-				Message:  resp.Header.Get(HeaderStatusMessage),
-				Status:   ResponseError,
-			},
-		}
-	}
-
-	// Get filename from headers
-	serverFileName := resp.Header.Get(HeaderFileName)
-	// Get file checksum from headers
-	checksum := resp.Header.Get(HeaderChecksum)
-
-	// Check headers
-	if len(serverFileName) == 0 {
-		return nil, "", "", &ResponseErr{
-			Err: ErrResponseFilenameInvalid,
-		}
-	}
-
-	return resp, serverFileName, checksum, nil
-}
-
-var (
-	// ErrChecksumNotMatch error if the checksum of the downloaded
-	// file doesn't match with the checksum of the remote file
-	ErrChecksumNotMatch = errors.New("generated checksum not match")
-)
-
-// DownloadFile downloads and saves a file to the given localFilePath. If the file exists, it will be overwritten
-func (libdm LibDM) DownloadFile(name string, id uint, namespace, localFilePath string, appendFilename ...bool) error {
-	// Download file from server
-	resp, name, checksum, err := libdm.GetFile(name, id, namespace)
-	if err != nil {
-		return err
-	}
-	defer resp.Body.Close()
-
-	hash := crc32.NewIEEE()
-
-	// Append remote filename if desired
-	if len(appendFilename) > 0 && appendFilename[0] {
-		localFilePath = filepath.Join(localFilePath, name)
-	}
-
-	// Create loal file
-	f, err := os.Create(localFilePath)
-	defer f.Close()
-	if err != nil {
-		return err
-	}
-
-	w := io.MultiWriter(hash, f)
-
-	// Save file to local file
-	buff := make([]byte, 10*1024)
-	_, err = io.CopyBuffer(w, resp.Body, buff)
-	if err != nil {
-		return err
-	}
-
-	// Check if the checksums are equal, if not return an error
-	if hex.EncodeToString(hash.Sum(nil)) != checksum {
-		return ErrChecksumNotMatch
-	}
-
-	return nil
-}
-
 // UpdateFile updates a file on the server
 func (libdm LibDM) UpdateFile(name string, id uint, namespace string, all bool, changes FileChanges) (*CountResponse, error) {
 	// Set attributes
@@ -239,6 +152,7 @@ func (libdm LibDM) UpdateFile(name string, id uint, namespace string, all bool,
 
 	var response CountResponse
 
+	// Do request
 	if _, err := libdm.Request(EPFileUpdate, &FileRequest{
 		Name:       name,
 		FileID:     id,