remove all debug

test
details
2024-01-20 12:33:07 +01:00 · 2024-01-20 12:18:22 +01:00 · 2024-01-20 12:11:08 +01:00 · 2024-01-20 12:06:08 +01:00 · 2024-01-20 12:05:02 +01:00 · 2024-01-20 11:59:18 +01:00
17 changed files with 1397 additions and 269 deletions
--- a/.github/workflows/tests.yml
+++ b/.github/workflows/tests.yml
@ -15,9 +15,9 @@ jobs:
    strategy:
      matrix:
        goversion:
+          - "1.20"
          - "1.19"
          - "1.18"
-          - "1.17"
    steps:
      - name: Set up Go
        uses: actions/setup-go@v1
--- a/17
+++ b/17
@ -11,22 +11,31 @@ ${BIN}: ${SRC}
 test:
 	go test -modfile=go_test.mod -v -short -cover ./...

-api:
+api: .go/bin/godoc2md
 	@sed '/^## API$$/,$$d' -i README.md
 	@echo '## API' >> README.md
-	@godoc2md github.com/studio-b12/gowebdav | sed '/^$$/N;/^\n$$/D' |\
+	@$< github.com/studio-b12/gowebdav | sed '/^$$/N;/^\n$$/D' |\
 	sed '2d' |\
 	sed 's/\/src\/github.com\/studio-b12\/gowebdav\//https:\/\/github.com\/studio-b12\/gowebdav\/blob\/master\//g' |\
 	sed 's/\/src\/target\//https:\/\/github.com\/studio-b12\/gowebdav\/blob\/master\//g' |\
 	sed 's/^#/##/g' >> README.md

-check:
+check: .go/bin/gocyclo
 	gofmt -w -s $(SRC)
 	@echo
-	gocyclo -over 15 .
+	.go/bin/gocyclo -over 15 .
 	@echo
 	go vet -modfile=go_test.mod ./...

+
+.go/bin/godoc2md:
+	@mkdir -p $(@D)
+	@GOPATH="$(CURDIR)/.go" go install github.com/davecheney/godoc2md@latest
+
+.go/bin/gocyclo:
+	@mkdir -p $(@D)
+	@GOPATH="$(CURDIR)/.go" go install github.com/fzipp/gocyclo/cmd/gocyclo@latest
+
 clean:
 	@rm -f ${BIN}

--- a/README.md
+++ b/README.md
@ -5,11 +5,12 @@
 [![GoDoc](https://godoc.org/github.com/studio-b12/gowebdav?status.svg)](https://godoc.org/github.com/studio-b12/gowebdav)
 [![Go Report Card](https://goreportcard.com/badge/github.com/studio-b12/gowebdav)](https://goreportcard.com/report/github.com/studio-b12/gowebdav)

-A golang WebDAV client library.
+A pure Golang WebDAV client library that comes with a [reference implementation](https://github.com/studio-b12/gowebdav/tree/master/cmd/gowebdav).

-## Main features
+## Features at a glance
+
+Our `gowebdav` library allows to perform following actions on the remote WebDAV server:

-`gowebdav` library allows to perform following actions on the remote WebDAV server:
 * [create path](#create-path-on-a-webdav-server)
 * [get files list](#get-files-list)
 * [download file](#download-file-to-byte-array)
@ -19,6 +20,17 @@ A golang WebDAV client library.
 * [copy file to another location](#copy-file-to-another-location)
 * [delete file](#delete-file)

+It also provides an [authentication API](#type-authenticator) that makes it easy to encapsulate and control complex authentication challenges.
+The default implementation negotiates the algorithm based on the user's preferences and the methods offered by the remote server.
+
+Out-of-box authentication support for:
+
+* [BasicAuth](https://en.wikipedia.org/wiki/Basic_access_authentication)
+* [DigestAuth](https://en.wikipedia.org/wiki/Digest_access_authentication)
+* [MS-PASS](https://github.com/studio-b12/gowebdav/pull/70#issuecomment-1421713726)
+* [WIP Kerberos](https://github.com/studio-b12/gowebdav/pull/71#issuecomment-1416465334)
+* [WIP Bearer Token](https://github.com/studio-b12/gowebdav/issues/61)
+
 ## Usage

 First of all you should create `Client` instance using `NewClient()` function:
@ -29,11 +41,13 @@ user := "user"
 password := "password"

 c := gowebdav.NewClient(root, user, password)
+c.Connect()
+// kick of your work!
 ```

 After you can use this `Client` to perform actions, described below.

-**NOTICE:** we will not check errors in examples, to focus you on the `gowebdav` library's code, but you should do it in your code!
+**NOTICE:** We will not check for errors in the examples, to focus you on the `gowebdav` library's code, but you should do it in your code!

 ### Create path on a WebDAV server
 ```go
@ -59,7 +73,7 @@ webdavFilePath := "folder/subfolder/file.txt"
 localFilePath := "/tmp/webdav/file.txt"

 bytes, _ := c.Read(webdavFilePath)
-ioutil.WriteFile(localFilePath, bytes, 0644)
+os.WriteFile(localFilePath, bytes, 0644)
 ```

 ### Download file via reader
@ -81,7 +95,7 @@ io.Copy(file, reader)
 webdavFilePath := "folder/subfolder/file.txt"
 localFilePath := "/tmp/webdav/file.txt"

-bytes, _ := ioutil.ReadFile(localFilePath)
+bytes, _ := os.ReadFile(localFilePath)

 c.Write(webdavFilePath, bytes, 0644)
 ```
@ -161,21 +175,34 @@ Package gowebdav is a WebDAV client library with a command line tool
 included.

 ### <a name="pkg-index">Index</a>
+* [Constants](#pkg-constants)
+* [Variables](#pkg-variables)
 * [func FixSlash(s string) string](#FixSlash)
 * [func FixSlashes(s string) string](#FixSlashes)
 * [func IsErrCode(err error, code int) bool](#IsErrCode)
 * [func IsErrNotFound(err error) bool](#IsErrNotFound)
 * [func Join(path0 string, path1 string) string](#Join)
+* [func NewPathError(op string, path string, statusCode int) error](#NewPathError)
+* [func NewPathErrorErr(op string, path string, err error) error](#NewPathErrorErr)
 * [func PathEscape(path string) string](#PathEscape)
 * [func ReadConfig(uri, netrc string) (string, string)](#ReadConfig)
 * [func String(r io.Reader) string](#String)
+* [type AuthFactory](#AuthFactory)
 * [type Authenticator](#Authenticator)
+  * [func NewDigestAuth(login, secret string, rs *http.Response) (Authenticator, error)](#NewDigestAuth)
+  * [func NewPassportAuth(c *http.Client, user, pw, partnerURL string, header *http.Header) (Authenticator, error)](#NewPassportAuth)
+* [type Authorizer](#Authorizer)
+  * [func NewAutoAuth(login string, secret string) Authorizer](#NewAutoAuth)
+  * [func NewEmptyAuth() Authorizer](#NewEmptyAuth)
+  * [func NewPreemptiveAuth(auth Authenticator) Authorizer](#NewPreemptiveAuth)
 * [type BasicAuth](#BasicAuth)
-  * [func (b *BasicAuth) Authorize(req *http.Request, method string, path string)](#BasicAuth.Authorize)
-  * [func (b *BasicAuth) Pass() string](#BasicAuth.Pass)
-  * [func (b *BasicAuth) Type() string](#BasicAuth.Type)
-  * [func (b *BasicAuth) User() string](#BasicAuth.User)
+  * [func (b *BasicAuth) Authorize(c *http.Client, rq *http.Request, path string) error](#BasicAuth.Authorize)
+  * [func (b *BasicAuth) Clone() Authenticator](#BasicAuth.Clone)
+  * [func (b *BasicAuth) Close() error](#BasicAuth.Close)
+  * [func (b *BasicAuth) String() string](#BasicAuth.String)
+  * [func (b *BasicAuth) Verify(c *http.Client, rs *http.Response, path string) (redo bool, err error)](#BasicAuth.Verify)
 * [type Client](#Client)
+  * [func NewAuthClient(uri string, auth Authorizer) *Client](#NewAuthClient)
  * [func NewClient(uri, user, pw string) *Client](#NewClient)
  * [func (c *Client) Connect() error](#Client.Connect)
  * [func (c *Client) Copy(oldpath, newpath string, overwrite bool) error](#Client.Copy)
@ -190,16 +217,18 @@ included.
  * [func (c *Client) Rename(oldpath, newpath string, overwrite bool) error](#Client.Rename)
  * [func (c *Client) SetHeader(key, value string)](#Client.SetHeader)
  * [func (c *Client) SetInterceptor(interceptor func(method string, rq *http.Request))](#Client.SetInterceptor)
+  * [func (c *Client) SetJar(jar http.CookieJar)](#Client.SetJar)
  * [func (c *Client) SetTimeout(timeout time.Duration)](#Client.SetTimeout)
  * [func (c *Client) SetTransport(transport http.RoundTripper)](#Client.SetTransport)
  * [func (c *Client) Stat(path string) (os.FileInfo, error)](#Client.Stat)
  * [func (c *Client) Write(path string, data []byte, _ os.FileMode) (err error)](#Client.Write)
  * [func (c *Client) WriteStream(path string, stream io.Reader, _ os.FileMode) (err error)](#Client.WriteStream)
 * [type DigestAuth](#DigestAuth)
-  * [func (d *DigestAuth) Authorize(req *http.Request, method string, path string)](#DigestAuth.Authorize)
-  * [func (d *DigestAuth) Pass() string](#DigestAuth.Pass)
-  * [func (d *DigestAuth) Type() string](#DigestAuth.Type)
-  * [func (d *DigestAuth) User() string](#DigestAuth.User)
+  * [func (d *DigestAuth) Authorize(c *http.Client, rq *http.Request, path string) error](#DigestAuth.Authorize)
+  * [func (d *DigestAuth) Clone() Authenticator](#DigestAuth.Clone)
+  * [func (d *DigestAuth) Close() error](#DigestAuth.Close)
+  * [func (d *DigestAuth) String() string](#DigestAuth.String)
+  * [func (d *DigestAuth) Verify(c *http.Client, rs *http.Response, path string) (redo bool, err error)](#DigestAuth.Verify)
 * [type File](#File)
  * [func (f File) ContentType() string](#File.ContentType)
  * [func (f File) ETag() string](#File.ETag)
@ -211,11 +240,12 @@ included.
  * [func (f File) Size() int64](#File.Size)
  * [func (f File) String() string](#File.String)
  * [func (f File) Sys() interface{}](#File.Sys)
-* [type NoAuth](#NoAuth)
-  * [func (n *NoAuth) Authorize(req *http.Request, method string, path string)](#NoAuth.Authorize)
-  * [func (n *NoAuth) Pass() string](#NoAuth.Pass)
-  * [func (n *NoAuth) Type() string](#NoAuth.Type)
-  * [func (n *NoAuth) User() string](#NoAuth.User)
+* [type PassportAuth](#PassportAuth)
+  * [func (p *PassportAuth) Authorize(c *http.Client, rq *http.Request, path string) error](#PassportAuth.Authorize)
+  * [func (p *PassportAuth) Clone() Authenticator](#PassportAuth.Clone)
+  * [func (p *PassportAuth) Close() error](#PassportAuth.Close)
+  * [func (p *PassportAuth) String() string](#PassportAuth.String)
+  * [func (p *PassportAuth) Verify(c *http.Client, rs *http.Response, path string) (redo bool, err error)](#PassportAuth.Verify)
 * [type StatusError](#StatusError)
  * [func (se StatusError) Error() string](#StatusError.Error)

@ -223,7 +253,24 @@ included.
 * [PathEscape](#example_PathEscape)

 ##### <a name="pkg-files">Package files</a>
-[basicAuth.go](https://github.com/studio-b12/gowebdav/blob/master/basicAuth.go) [client.go](https://github.com/studio-b12/gowebdav/blob/master/client.go) [digestAuth.go](https://github.com/studio-b12/gowebdav/blob/master/digestAuth.go) [doc.go](https://github.com/studio-b12/gowebdav/blob/master/doc.go) [errors.go](https://github.com/studio-b12/gowebdav/blob/master/errors.go) [file.go](https://github.com/studio-b12/gowebdav/blob/master/file.go) [netrc.go](https://github.com/studio-b12/gowebdav/blob/master/netrc.go) [requests.go](https://github.com/studio-b12/gowebdav/blob/master/requests.go) [utils.go](https://github.com/studio-b12/gowebdav/blob/master/utils.go) 
+[auth.go](https://github.com/studio-b12/gowebdav/blob/master/auth.go) [basicAuth.go](https://github.com/studio-b12/gowebdav/blob/master/basicAuth.go) [client.go](https://github.com/studio-b12/gowebdav/blob/master/client.go) [digestAuth.go](https://github.com/studio-b12/gowebdav/blob/master/digestAuth.go) [doc.go](https://github.com/studio-b12/gowebdav/blob/master/doc.go) [errors.go](https://github.com/studio-b12/gowebdav/blob/master/errors.go) [file.go](https://github.com/studio-b12/gowebdav/blob/master/file.go) [netrc.go](https://github.com/studio-b12/gowebdav/blob/master/netrc.go) [passportAuth.go](https://github.com/studio-b12/gowebdav/blob/master/passportAuth.go) [requests.go](https://github.com/studio-b12/gowebdav/blob/master/requests.go) [utils.go](https://github.com/studio-b12/gowebdav/blob/master/utils.go) 
+
+### <a name="pkg-constants">Constants</a>
+``` go
+const XInhibitRedirect = "X-Gowebdav-Inhibit-Redirect"
+```
+
+### <a name="pkg-variables">Variables</a>
+``` go
+var ErrAuthChanged = errors.New("authentication failed, change algorithm")
+```
+ErrAuthChanged must be returned from the Verify method as an error
+to trigger a re-authentication / negotiation with a new authenticator.
+
+``` go
+var ErrTooManyRedirects = errors.New("stopped after 10 redirects")
+```
+ErrTooManyRedirects will be used as return error if a request exceeds 10 redirects.

 ### <a name="FixSlash">func</a> [FixSlash](https://github.com/studio-b12/gowebdav/blob/master/utils.go?s=354:384#L23)
 ``` go
@ -237,7 +284,7 @@ func FixSlashes(s string) string
 ```
 FixSlashes appends and prepends a / if they are missing

-### <a name="IsErrCode">func</a> [IsErrCode](https://github.com/studio-b12/gowebdav/blob/master/errors.go?s=355:395#L21)
+### <a name="IsErrCode">func</a> [IsErrCode](https://github.com/studio-b12/gowebdav/blob/master/errors.go?s=740:780#L29)
 ``` go
 func IsErrCode(err error, code int) bool
 ```
@ -245,7 +292,7 @@ IsErrCode returns true if the given error
 is an os.PathError wrapping a StatusError
 with the given status code.

-### <a name="IsErrNotFound">func</a> [IsErrNotFound](https://github.com/studio-b12/gowebdav/blob/master/errors.go?s=587:621#L31)
+### <a name="IsErrNotFound">func</a> [IsErrNotFound](https://github.com/studio-b12/gowebdav/blob/master/errors.go?s=972:1006#L39)
 ``` go
 func IsErrNotFound(err error) bool
 ```
@ -258,6 +305,16 @@ func Join(path0 string, path1 string) string
 ```
 Join joins two paths

+### <a name="NewPathError">func</a> [NewPathError](https://github.com/studio-b12/gowebdav/blob/master/errors.go?s=1040:1103#L43)
+``` go
+func NewPathError(op string, path string, statusCode int) error
+```
+
+### <a name="NewPathErrorErr">func</a> [NewPathErrorErr](https://github.com/studio-b12/gowebdav/blob/master/errors.go?s=1194:1255#L51)
+``` go
+func NewPathErrorErr(op string, path string, err error) error
+```
+
 ### <a name="PathEscape">func</a> [PathEscape](https://github.com/studio-b12/gowebdav/blob/master/utils.go?s=153:188#L14)
 ``` go
 func PathEscape(path string) string
@ -277,18 +334,119 @@ func String(r io.Reader) string
 ```
 String pulls a string out of our io.Reader

-### <a name="Authenticator">type</a> [Authenticator](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=388:507#L29)
+### <a name="AuthFactory">type</a> [AuthFactory](https://github.com/studio-b12/gowebdav/blob/master/auth.go?s=150:251#L13)
+``` go
+type AuthFactory func(c *http.Client, rs *http.Response, path string) (auth Authenticator, err error)
+```
+AuthFactory prototype function to create a new Authenticator
+
+### <a name="Authenticator">type</a> [Authenticator](https://github.com/studio-b12/gowebdav/blob/master/auth.go?s=2155:2695#L56)
 ``` go
 type Authenticator interface {
-    Type() string
-    User() string
-    Pass() string
-    Authorize(*http.Request, string, string)
+    // Authorizes a request. Usually by adding some authorization headers.
+    Authorize(c *http.Client, rq *http.Request, path string) error
+    // Verifies the response if the authorization was successful.
+    // May trigger some round trips to pass the authentication.
+    // May also trigger a new Authenticator negotiation by returning `ErrAuthChenged`
+    Verify(c *http.Client, rs *http.Response, path string) (redo bool, err error)
+    // Creates a copy of the underlying Authenticator.
+    Clone() Authenticator
+    io.Closer
 }
 ```
-Authenticator stub
+A Authenticator implements a specific way to authorize requests.
+Each request is bound to a separate Authenticator instance.

-### <a name="BasicAuth">type</a> [BasicAuth](https://github.com/studio-b12/gowebdav/blob/master/basicAuth.go?s=106:157#L9)
+The authentication flow itself is broken down into `Authorize`
+and `Verify` steps. The former method runs before, and the latter
+runs after the `Request` is submitted.
+This makes it easy to encapsulate and control complex
+authentication challenges.
+
+Some authentication flows causing authentication round trips,
+which can be archived by returning the `redo` of the Verify
+method. `True` restarts the authentication process for the
+current action: A new `Request` is spawned, which must be
+authorized, sent, and re-verified again, until the action
+is successfully submitted.
+The preferred way is to handle the authentication ping-pong
+within `Verify`, and then `redo` with fresh credentials.
+
+The result of the `Verify` method can also trigger an
+`Authenticator` change by returning the `ErrAuthChanged`
+as an error. Depending on the `Authorizer` this may trigger
+an `Authenticator` negotiation.
+
+Set the `XInhibitRedirect` header to '1' in the `Authorize`
+method to get control over request redirection.
+Attention! You must handle the incoming request yourself.
+
+To store a shared session state the `Clone` method **must**
+return a new instance, initialized with the shared state.
+
+#### <a name="NewDigestAuth">func</a> [NewDigestAuth](https://github.com/studio-b12/gowebdav/blob/master/digestAuth.go?s=324:406#L21)
+``` go
+func NewDigestAuth(login, secret string, rs *http.Response) (Authenticator, error)
+```
+NewDigestAuth creates a new instance of our Digest Authenticator
+
+#### <a name="NewPassportAuth">func</a> [NewPassportAuth](https://github.com/studio-b12/gowebdav/blob/master/passportAuth.go?s=386:495#L21)
+``` go
+func NewPassportAuth(c *http.Client, user, pw, partnerURL string, header *http.Header) (Authenticator, error)
+```
+constructor for PassportAuth creates a new PassportAuth object and
+automatically authenticates against the given partnerURL
+
+### <a name="Authorizer">type</a> [Authorizer](https://github.com/studio-b12/gowebdav/blob/master/auth.go?s=349:764#L17)
+``` go
+type Authorizer interface {
+    // Creates a new Authenticator Shim per request.
+    // It may track request related states and perform payload buffering
+    // for authentication round trips.
+    // The underlying Authenticator will perform the real authentication.
+    NewAuthenticator(body io.Reader) (Authenticator, io.Reader)
+    // Registers a new Authenticator factory to a key.
+    AddAuthenticator(key string, fn AuthFactory)
+}
+```
+Authorizer our Authenticator factory which creates an
+`Authenticator` per action/request.
+
+#### <a name="NewAutoAuth">func</a> [NewAutoAuth](https://github.com/studio-b12/gowebdav/blob/master/auth.go?s=3789:3845#L109)
+``` go
+func NewAutoAuth(login string, secret string) Authorizer
+```
+NewAutoAuth creates an auto Authenticator factory.
+It negotiates the default authentication method
+based on the order of the registered Authenticators
+and the remotely offered authentication methods.
+First In, First Out.
+
+#### <a name="NewEmptyAuth">func</a> [NewEmptyAuth](https://github.com/studio-b12/gowebdav/blob/master/auth.go?s=4694:4724#L132)
+``` go
+func NewEmptyAuth() Authorizer
+```
+NewEmptyAuth creates an empty Authenticator factory
+The order of adding the Authenticator matters.
+First In, First Out.
+It offers the `NewAutoAuth` features.
+
+#### <a name="NewPreemptiveAuth">func</a> [NewPreemptiveAuth](https://github.com/studio-b12/gowebdav/blob/master/auth.go?s=5300:5353#L148)
+``` go
+func NewPreemptiveAuth(auth Authenticator) Authorizer
+```
+NewPreemptiveAuth creates a preemptive Authenticator
+The preemptive authorizer uses the provided Authenticator
+for every request regardless of any `Www-Authenticate` header.
+
+It may only have one authentication method,
+so calling `AddAuthenticator` **will panic**!
+
+Look out!! This offers the skinniest and slickest implementation
+without any synchronisation!!
+Still applicable with `BasicAuth` within go routines.
+
+### <a name="BasicAuth">type</a> [BasicAuth](https://github.com/studio-b12/gowebdav/blob/master/basicAuth.go?s=94:145#L9)
 ``` go
 type BasicAuth struct {
    // contains filtered or unexported fields
@ -297,31 +455,37 @@ type BasicAuth struct {
 ```
 BasicAuth structure holds our credentials

-#### <a name="BasicAuth.Authorize">func</a> (\*BasicAuth) [Authorize](https://github.com/studio-b12/gowebdav/blob/master/basicAuth.go?s=473:549#L30)
+#### <a name="BasicAuth.Authorize">func</a> (\*BasicAuth) [Authorize](https://github.com/studio-b12/gowebdav/blob/master/basicAuth.go?s=180:262#L15)
 ``` go
-func (b *BasicAuth) Authorize(req *http.Request, method string, path string)
+func (b *BasicAuth) Authorize(c *http.Client, rq *http.Request, path string) error
 ```
 Authorize the current request

-#### <a name="BasicAuth.Pass">func</a> (\*BasicAuth) [Pass](https://github.com/studio-b12/gowebdav/blob/master/basicAuth.go?s=388:421#L25)
+#### <a name="BasicAuth.Clone">func</a> (\*BasicAuth) [Clone](https://github.com/studio-b12/gowebdav/blob/master/basicAuth.go?s=666:707#L34)
 ``` go
-func (b *BasicAuth) Pass() string
+func (b *BasicAuth) Clone() Authenticator
 ```
-Pass holds the BasicAuth password
+Clone creates a Copy of itself

-#### <a name="BasicAuth.Type">func</a> (\*BasicAuth) [Type](https://github.com/studio-b12/gowebdav/blob/master/basicAuth.go?s=201:234#L15)
+#### <a name="BasicAuth.Close">func</a> (\*BasicAuth) [Close](https://github.com/studio-b12/gowebdav/blob/master/basicAuth.go?s=581:614#L29)
 ``` go
-func (b *BasicAuth) Type() string
+func (b *BasicAuth) Close() error
 ```
-Type identifies the BasicAuthenticator
+Close cleans up all resources

-#### <a name="BasicAuth.User">func</a> (\*BasicAuth) [User](https://github.com/studio-b12/gowebdav/blob/master/basicAuth.go?s=297:330#L20)
+#### <a name="BasicAuth.String">func</a> (\*BasicAuth) [String](https://github.com/studio-b12/gowebdav/blob/master/basicAuth.go?s=778:813#L40)
 ``` go
-func (b *BasicAuth) User() string
+func (b *BasicAuth) String() string
 ```
-User holds the BasicAuth username
+String toString

-### <a name="Client">type</a> [Client](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=172:364#L18)
+#### <a name="BasicAuth.Verify">func</a> (\*BasicAuth) [Verify](https://github.com/studio-b12/gowebdav/blob/master/basicAuth.go?s=352:449#L21)
+``` go
+func (b *BasicAuth) Verify(c *http.Client, rs *http.Response, path string) (redo bool, err error)
+```
+Verify verifies if the authentication
+
+### <a name="Client">type</a> [Client](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=220:388#L19)
 ``` go
 type Client struct {
    // contains filtered or unexported fields
@ -330,55 +494,61 @@ type Client struct {
 ```
 Client defines our structure

-#### <a name="NewClient">func</a> [NewClient](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=1019:1063#L62)
+#### <a name="NewAuthClient">func</a> [NewAuthClient](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=608:663#L33)
+``` go
+func NewAuthClient(uri string, auth Authorizer) *Client
+```
+NewAuthClient creates a new client instance with a custom Authorizer
+
+#### <a name="NewClient">func</a> [NewClient](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=436:480#L28)
 ``` go
 func NewClient(uri, user, pw string) *Client
 ```
 NewClient creates a new instance of client

-#### <a name="Client.Connect">func</a> (\*Client) [Connect](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=1843:1875#L87)
+#### <a name="Client.Connect">func</a> (\*Client) [Connect](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=1829:1861#L74)
 ``` go
 func (c *Client) Connect() error
 ```
 Connect connects to our dav server

-#### <a name="Client.Copy">func</a> (\*Client) [Copy](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=6818:6886#L323)
+#### <a name="Client.Copy">func</a> (\*Client) [Copy](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=6815:6883#L310)
 ``` go
 func (c *Client) Copy(oldpath, newpath string, overwrite bool) error
 ```
 Copy copies a file from A to B

-#### <a name="Client.Mkdir">func</a> (\*Client) [Mkdir](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=5793:5855#L272)
+#### <a name="Client.Mkdir">func</a> (\*Client) [Mkdir](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=5790:5852#L259)
 ``` go
 func (c *Client) Mkdir(path string, _ os.FileMode) (err error)
 ```
 Mkdir makes a directory

-#### <a name="Client.MkdirAll">func</a> (\*Client) [MkdirAll](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=6068:6133#L286)
+#### <a name="Client.MkdirAll">func</a> (\*Client) [MkdirAll](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=6065:6130#L273)
 ``` go
 func (c *Client) MkdirAll(path string, _ os.FileMode) (err error)
 ```
 MkdirAll like mkdir -p, but for webdav

-#### <a name="Client.Read">func</a> (\*Client) [Read](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=6992:7042#L328)
+#### <a name="Client.Read">func</a> (\*Client) [Read](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=6989:7039#L315)
 ``` go
 func (c *Client) Read(path string) ([]byte, error)
 ```
 Read reads the contents of a remote file

-#### <a name="Client.ReadDir">func</a> (\*Client) [ReadDir](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=2869:2929#L130)
+#### <a name="Client.ReadDir">func</a> (\*Client) [ReadDir](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=2855:2915#L117)
 ``` go
 func (c *Client) ReadDir(path string) ([]os.FileInfo, error)
 ```
 ReadDir reads the contents of a remote directory

-#### <a name="Client.ReadStream">func</a> (\*Client) [ReadStream](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=7353:7416#L346)
+#### <a name="Client.ReadStream">func</a> (\*Client) [ReadStream](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=7350:7413#L333)
 ``` go
 func (c *Client) ReadStream(path string) (io.ReadCloser, error)
 ```
 ReadStream reads the stream for a given path

-#### <a name="Client.ReadStreamRange">func</a> (\*Client) [ReadStreamRange](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=8165:8255#L368)
+#### <a name="Client.ReadStreamRange">func</a> (\*Client) [ReadStreamRange](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=8162:8252#L355)
 ``` go
 func (c *Client) ReadStreamRange(path string, offset, length int64) (io.ReadCloser, error)
 ```
@ -391,61 +561,67 @@ If the server does not support partial content requests and returns full content
 this function will emulate the behavior by skipping `offset` bytes and limiting the result
 to `length`.

-#### <a name="Client.Remove">func</a> (\*Client) [Remove](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=5299:5341#L249)
+#### <a name="Client.Remove">func</a> (\*Client) [Remove](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=5296:5338#L236)
 ``` go
 func (c *Client) Remove(path string) error
 ```
 Remove removes a remote file

-#### <a name="Client.RemoveAll">func</a> (\*Client) [RemoveAll](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=5407:5452#L254)
+#### <a name="Client.RemoveAll">func</a> (\*Client) [RemoveAll](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=5404:5449#L241)
 ``` go
 func (c *Client) RemoveAll(path string) error
 ```
 RemoveAll removes remote files

-#### <a name="Client.Rename">func</a> (\*Client) [Rename](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=6652:6722#L318)
+#### <a name="Client.Rename">func</a> (\*Client) [Rename](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=6649:6719#L305)
 ``` go
 func (c *Client) Rename(oldpath, newpath string, overwrite bool) error
 ```
 Rename moves a file from A to B

-#### <a name="Client.SetHeader">func</a> (\*Client) [SetHeader](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=1235:1280#L67)
+#### <a name="Client.SetHeader">func</a> (\*Client) [SetHeader](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=1092:1137#L49)
 ``` go
 func (c *Client) SetHeader(key, value string)
 ```
 SetHeader lets us set arbitrary headers for a given client

-#### <a name="Client.SetInterceptor">func</a> (\*Client) [SetInterceptor](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=1387:1469#L72)
+#### <a name="Client.SetInterceptor">func</a> (\*Client) [SetInterceptor](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=1244:1326#L54)
 ``` go
 func (c *Client) SetInterceptor(interceptor func(method string, rq *http.Request))
 ```
 SetInterceptor lets us set an arbitrary interceptor for a given client

-#### <a name="Client.SetTimeout">func</a> (\*Client) [SetTimeout](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=1571:1621#L77)
+#### <a name="Client.SetJar">func</a> (\*Client) [SetJar](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=1727:1770#L69)
+``` go
+func (c *Client) SetJar(jar http.CookieJar)
+```
+SetJar exposes the ability to set a cookie jar to the client.
+
+#### <a name="Client.SetTimeout">func</a> (\*Client) [SetTimeout](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=1428:1478#L59)
 ``` go
 func (c *Client) SetTimeout(timeout time.Duration)
 ```
 SetTimeout exposes the ability to set a time limit for requests

-#### <a name="Client.SetTransport">func</a> (\*Client) [SetTransport](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=1714:1772#L82)
+#### <a name="Client.SetTransport">func</a> (\*Client) [SetTransport](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=1571:1629#L64)
 ``` go
 func (c *Client) SetTransport(transport http.RoundTripper)
 ```
 SetTransport exposes the ability to define custom transports

-#### <a name="Client.Stat">func</a> (\*Client) [Stat](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=4255:4310#L197)
+#### <a name="Client.Stat">func</a> (\*Client) [Stat](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=4241:4296#L184)
 ``` go
 func (c *Client) Stat(path string) (os.FileInfo, error)
 ```
 Stat returns the file stats for a specified path

-#### <a name="Client.Write">func</a> (\*Client) [Write](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=9260:9335#L402)
+#### <a name="Client.Write">func</a> (\*Client) [Write](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=9272:9347#L389)
 ``` go
 func (c *Client) Write(path string, data []byte, _ os.FileMode) (err error)
 ```
 Write writes data to a given path

-#### <a name="Client.WriteStream">func</a> (\*Client) [WriteStream](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=9759:9845#L432)
+#### <a name="Client.WriteStream">func</a> (\*Client) [WriteStream](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=9771:9857#L419)
 ``` go
 func (c *Client) WriteStream(path string, stream io.Reader, _ os.FileMode) (err error)
 ```
@ -460,29 +636,35 @@ type DigestAuth struct {
 ```
 DigestAuth structure holds our credentials

-#### <a name="DigestAuth.Authorize">func</a> (\*DigestAuth) [Authorize](https://github.com/studio-b12/gowebdav/blob/master/digestAuth.go?s=577:654#L36)
+#### <a name="DigestAuth.Authorize">func</a> (\*DigestAuth) [Authorize](https://github.com/studio-b12/gowebdav/blob/master/digestAuth.go?s=525:608#L26)
 ``` go
-func (d *DigestAuth) Authorize(req *http.Request, method string, path string)
+func (d *DigestAuth) Authorize(c *http.Client, rq *http.Request, path string) error
 ```
 Authorize the current request

-#### <a name="DigestAuth.Pass">func</a> (\*DigestAuth) [Pass](https://github.com/studio-b12/gowebdav/blob/master/digestAuth.go?s=491:525#L31)
+#### <a name="DigestAuth.Clone">func</a> (\*DigestAuth) [Clone](https://github.com/studio-b12/gowebdav/blob/master/digestAuth.go?s=1228:1270#L49)
 ``` go
-func (d *DigestAuth) Pass() string
+func (d *DigestAuth) Clone() Authenticator
 ```
-Pass holds the DigestAuth password
+Clone creates a copy of itself

-#### <a name="DigestAuth.Type">func</a> (\*DigestAuth) [Type](https://github.com/studio-b12/gowebdav/blob/master/digestAuth.go?s=299:333#L21)
+#### <a name="DigestAuth.Close">func</a> (\*DigestAuth) [Close](https://github.com/studio-b12/gowebdav/blob/master/digestAuth.go?s=1142:1176#L44)
 ``` go
-func (d *DigestAuth) Type() string
+func (d *DigestAuth) Close() error
 ```
-Type identifies the DigestAuthenticator
+Close cleans up all resources

-#### <a name="DigestAuth.User">func</a> (\*DigestAuth) [User](https://github.com/studio-b12/gowebdav/blob/master/digestAuth.go?s=398:432#L26)
+#### <a name="DigestAuth.String">func</a> (\*DigestAuth) [String](https://github.com/studio-b12/gowebdav/blob/master/digestAuth.go?s=1466:1502#L58)
 ``` go
-func (d *DigestAuth) User() string
+func (d *DigestAuth) String() string
 ```
-User holds the DigestAuth username
+String toString
+
+#### <a name="DigestAuth.Verify">func</a> (\*DigestAuth) [Verify](https://github.com/studio-b12/gowebdav/blob/master/digestAuth.go?s=912:1010#L36)
+``` go
+func (d *DigestAuth) Verify(c *http.Client, rs *http.Response, path string) (redo bool, err error)
+```
+Verify checks for authentication issues and may trigger a re-authentication

 ### <a name="File">type</a> [File](https://github.com/studio-b12/gowebdav/blob/master/file.go?s=93:253#L10)
 ``` go
@ -553,40 +735,46 @@ func (f File) Sys() interface{}
 ```
 Sys ????

-### <a name="NoAuth">type</a> [NoAuth](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=551:599#L37)
+### <a name="PassportAuth">type</a> [PassportAuth](https://github.com/studio-b12/gowebdav/blob/master/passportAuth.go?s=125:254#L12)
 ``` go
-type NoAuth struct {
+type PassportAuth struct {
    // contains filtered or unexported fields
 }

 ```
-NoAuth structure holds our credentials
+PassportAuth structure holds our credentials

-#### <a name="NoAuth.Authorize">func</a> (\*NoAuth) [Authorize](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=894:967#L58)
+#### <a name="PassportAuth.Authorize">func</a> (\*PassportAuth) [Authorize](https://github.com/studio-b12/gowebdav/blob/master/passportAuth.go?s=690:775#L32)
 ``` go
-func (n *NoAuth) Authorize(req *http.Request, method string, path string)
+func (p *PassportAuth) Authorize(c *http.Client, rq *http.Request, path string) error
 ```
 Authorize the current request

-#### <a name="NoAuth.Pass">func</a> (\*NoAuth) [Pass](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=812:842#L53)
+#### <a name="PassportAuth.Clone">func</a> (\*PassportAuth) [Clone](https://github.com/studio-b12/gowebdav/blob/master/passportAuth.go?s=1701:1745#L69)
 ``` go
-func (n *NoAuth) Pass() string
+func (p *PassportAuth) Clone() Authenticator
 ```
-Pass returns the current password
+Clone creates a Copy of itself

-#### <a name="NoAuth.Type">func</a> (\*NoAuth) [Type](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=638:668#L43)
+#### <a name="PassportAuth.Close">func</a> (\*PassportAuth) [Close](https://github.com/studio-b12/gowebdav/blob/master/passportAuth.go?s=1613:1649#L64)
 ``` go
-func (n *NoAuth) Type() string
+func (p *PassportAuth) Close() error
 ```
-Type identifies the authenticator
+Close cleans up all resources

-#### <a name="NoAuth.User">func</a> (\*NoAuth) [User](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=724:754#L48)
+#### <a name="PassportAuth.String">func</a> (\*PassportAuth) [String](https://github.com/studio-b12/gowebdav/blob/master/passportAuth.go?s=2048:2086#L83)
 ``` go
-func (n *NoAuth) User() string
+func (p *PassportAuth) String() string
 ```
-User returns the current user
+String toString

-### <a name="StatusError">type</a> [StatusError](https://github.com/studio-b12/gowebdav/blob/master/errors.go?s=114:153#L10)
+#### <a name="PassportAuth.Verify">func</a> (\*PassportAuth) [Verify](https://github.com/studio-b12/gowebdav/blob/master/passportAuth.go?s=1075:1175#L46)
+``` go
+func (p *PassportAuth) Verify(c *http.Client, rs *http.Response, path string) (redo bool, err error)
+```
+Verify verifies if the authentication is good
+
+### <a name="StatusError">type</a> [StatusError](https://github.com/studio-b12/gowebdav/blob/master/errors.go?s=499:538#L18)
 ``` go
 type StatusError struct {
    Status int
@ -596,7 +784,7 @@ type StatusError struct {
 StatusError implements error and wraps
 an erroneous status code.

-#### <a name="StatusError.Error">func</a> (StatusError) [Error](https://github.com/studio-b12/gowebdav/blob/master/errors.go?s=155:191#L14)
+#### <a name="StatusError.Error">func</a> (StatusError) [Error](https://github.com/studio-b12/gowebdav/blob/master/errors.go?s=540:576#L22)
 ``` go
 func (se StatusError) Error() string
 ```
--- a/auth.go
+++ b/auth.go
@ -0,0 +1,409 @@
+package gowebdav
+
+import (
+	"bytes"
+	"errors"
+	"io"
+	"net/http"
+	"strings"
+	"sync"
+)
+
+// AuthFactory prototype function to create a new Authenticator
+type AuthFactory func(c *http.Client, rs *http.Response, path string) (auth Authenticator, err error)
+
+// Authorizer our Authenticator factory which creates an
+// `Authenticator` per action/request.
+type Authorizer interface {
+	// Creates a new Authenticator Shim per request.
+	// It may track request related states and perform payload buffering
+	// for authentication round trips.
+	// The underlying Authenticator will perform the real authentication.
+	NewAuthenticator(body io.Reader) (Authenticator, io.Reader)
+	// Registers a new Authenticator factory to a key.
+	AddAuthenticator(key string, fn AuthFactory)
+}
+
+// A Authenticator implements a specific way to authorize requests.
+// Each request is bound to a separate Authenticator instance.
+//
+// The authentication flow itself is broken down into `Authorize`
+// and `Verify` steps. The former method runs before, and the latter
+// runs after the `Request` is submitted.
+// This makes it easy to encapsulate and control complex
+// authentication challenges.
+//
+// Some authentication flows causing authentication round trips,
+// which can be archived by returning the `redo` of the Verify
+// method. `True` restarts the authentication process for the
+// current action: A new `Request` is spawned, which must be
+// authorized, sent, and re-verified again, until the action
+// is successfully submitted.
+// The preferred way is to handle the authentication ping-pong
+// within `Verify`, and then `redo` with fresh credentials.
+//
+// The result of the `Verify` method can also trigger an
+// `Authenticator` change by returning the `ErrAuthChanged`
+// as an error. Depending on the `Authorizer` this may trigger
+// an `Authenticator` negotiation.
+//
+// Set the `XInhibitRedirect` header to '1' in the `Authorize`
+// method to get control over request redirection.
+// Attention! You must handle the incoming request yourself.
+//
+// To store a shared session state the `Clone` method **must**
+// return a new instance, initialized with the shared state.
+type Authenticator interface {
+	// Authorizes a request. Usually by adding some authorization headers.
+	Authorize(c *http.Client, rq *http.Request, path string) error
+	// Verifies the response if the authorization was successful.
+	// May trigger some round trips to pass the authentication.
+	// May also trigger a new Authenticator negotiation by returning `ErrAuthChenged`
+	Verify(c *http.Client, rs *http.Response, path string) (redo bool, err error)
+	// Creates a copy of the underlying Authenticator.
+	Clone() Authenticator
+	io.Closer
+}
+
+type authfactory struct {
+	key    string
+	create AuthFactory
+}
+
+// authorizer structure holds our Authenticator create functions
+type authorizer struct {
+	factories  []authfactory
+	defAuthMux sync.Mutex
+	defAuth    Authenticator
+}
+
+// preemptiveAuthorizer structure holds the preemptive Authenticator
+type preemptiveAuthorizer struct {
+	auth Authenticator
+}
+
+// authShim structure that wraps the real Authenticator
+type authShim struct {
+	factory AuthFactory
+	body    io.Reader
+	auth    Authenticator
+}
+
+// negoAuth structure holds the authenticators that are going to be negotiated
+type negoAuth struct {
+	auths                   []Authenticator
+	setDefaultAuthenticator func(auth Authenticator)
+}
+
+// nullAuth initializes the whole authentication flow
+type nullAuth struct{}
+
+// noAuth structure to perform no authentication at all
+type noAuth struct{}
+
+// NewAutoAuth creates an auto Authenticator factory.
+// It negotiates the default authentication method
+// based on the order of the registered Authenticators
+// and the remotely offered authentication methods.
+// First In, First Out.
+func NewAutoAuth(login string, secret string) Authorizer {
+	fmap := make([]authfactory, 0)
+	az := &authorizer{factories: fmap, defAuthMux: sync.Mutex{}, defAuth: &nullAuth{}}
+
+	az.AddAuthenticator("basic", func(c *http.Client, rs *http.Response, path string) (auth Authenticator, err error) {
+		return &BasicAuth{user: login, pw: secret}, nil
+	})
+
+	az.AddAuthenticator("digest", func(c *http.Client, rs *http.Response, path string) (auth Authenticator, err error) {
+		return NewDigestAuth(login, secret, rs)
+	})
+
+	az.AddAuthenticator("passport1.4", func(c *http.Client, rs *http.Response, path string) (auth Authenticator, err error) {
+		return NewPassportAuth(c, login, secret, rs.Request.URL.String(), &rs.Header)
+	})
+
+	return az
+}
+
+// NewEmptyAuth creates an empty Authenticator factory
+// The order of adding the Authenticator matters.
+// First In, First Out.
+// It offers the `NewAutoAuth` features.
+func NewEmptyAuth() Authorizer {
+	fmap := make([]authfactory, 0)
+	az := &authorizer{factories: fmap, defAuthMux: sync.Mutex{}, defAuth: &nullAuth{}}
+	return az
+}
+
+// NewPreemptiveAuth creates a preemptive Authenticator
+// The preemptive authorizer uses the provided Authenticator
+// for every request regardless of any `Www-Authenticate` header.
+//
+// It may only have one authentication method,
+// so calling `AddAuthenticator` **will panic**!
+//
+// Look out!! This offers the skinniest and slickest implementation
+// without any synchronisation!!
+// Still applicable with `BasicAuth` within go routines.
+func NewPreemptiveAuth(auth Authenticator) Authorizer {
+	return &preemptiveAuthorizer{auth: auth}
+}
+
+// NewAuthenticator creates an Authenticator (Shim) per request
+func (a *authorizer) NewAuthenticator(body io.Reader) (Authenticator, io.Reader) {
+	var retryBuf io.Reader = body
+	if body != nil {
+		// If the authorization fails, we will need to restart reading
+		// from the passed body stream.
+		// When body is seekable, use seek to reset the streams
+		// cursor to the start.
+		// Otherwise, copy the stream into a buffer while uploading
+		// and use the buffers content on retry.
+		if _, ok := retryBuf.(io.Seeker); ok {
+			body = io.NopCloser(body)
+		} else {
+			buff := &bytes.Buffer{}
+			retryBuf = buff
+			body = io.TeeReader(body, buff)
+		}
+	}
+	a.defAuthMux.Lock()
+	defAuth := a.defAuth.Clone()
+	a.defAuthMux.Unlock()
+
+	return &authShim{factory: a.factory, body: retryBuf, auth: defAuth}, body
+}
+
+// AddAuthenticator appends the AuthFactory to our factories.
+// It converts the key to lower case and preserves the order.
+func (a *authorizer) AddAuthenticator(key string, fn AuthFactory) {
+	key = strings.ToLower(key)
+	for _, f := range a.factories {
+		if f.key == key {
+			panic("Authenticator exists: " + key)
+		}
+	}
+	a.factories = append(a.factories, authfactory{key, fn})
+}
+
+// factory picks all valid Authenticators based on Www-Authenticate headers
+func (a *authorizer) factory(c *http.Client, rs *http.Response, path string) (auth Authenticator, err error) {
+	headers := rs.Header.Values("Www-Authenticate")
+	if len(headers) > 0 {
+		auths := make([]Authenticator, 0)
+		for _, f := range a.factories {
+			for _, header := range headers {
+				headerLower := strings.ToLower(header)
+				if strings.Contains(headerLower, f.key) {
+					rs.Header.Set("Www-Authenticate", header)
+					if auth, err = f.create(c, rs, path); err == nil {
+						auths = append(auths, auth)
+						break
+					}
+				}
+			}
+		}
+
+		switch len(auths) {
+		case 0:
+			return nil, NewPathError("NoAuthenticator", path, rs.StatusCode)
+		case 1:
+			auth = auths[0]
+		default:
+			auth = &negoAuth{auths: auths, setDefaultAuthenticator: a.setDefaultAuthenticator}
+		}
+	} else {
+		auth = &noAuth{}
+	}
+
+	a.setDefaultAuthenticator(auth)
+
+	return auth, nil
+}
+
+// setDefaultAuthenticator sets the default Authenticator
+func (a *authorizer) setDefaultAuthenticator(auth Authenticator) {
+	a.defAuthMux.Lock()
+	a.defAuth.Close()
+	a.defAuth = auth
+	a.defAuthMux.Unlock()
+}
+
+// Authorize the current request
+func (s *authShim) Authorize(c *http.Client, rq *http.Request, path string) error {
+	if err := s.auth.Authorize(c, rq, path); err != nil {
+		return err
+	}
+	body := s.body
+	rq.GetBody = func() (io.ReadCloser, error) {
+		if body != nil {
+			if sk, ok := body.(io.Seeker); ok {
+				if _, err := sk.Seek(0, io.SeekStart); err != nil {
+					return nil, err
+				}
+			}
+			return io.NopCloser(body), nil
+		}
+		return nil, nil
+	}
+	return nil
+}
+
+// Verify checks for authentication issues and may trigger a re-authentication.
+// Catches AlgoChangedErr to update the current Authenticator
+func (s *authShim) Verify(c *http.Client, rs *http.Response, path string) (redo bool, err error) {
+	redo, err = s.auth.Verify(c, rs, path)
+	if err != nil && errors.Is(err, ErrAuthChanged) {
+		if auth, aerr := s.factory(c, rs, path); aerr == nil {
+			s.auth.Close()
+			s.auth = auth
+			return true, nil
+		} else {
+			return false, aerr
+		}
+	}
+	return
+}
+
+// Close closes all resources
+func (s *authShim) Close() error {
+	s.auth.Close()
+	s.auth, s.factory = nil, nil
+	if s.body != nil {
+		if closer, ok := s.body.(io.Closer); ok {
+			return closer.Close()
+		}
+	}
+	return nil
+}
+
+// It's not intend to Clone the shim
+// therefore it returns a noAuth instance
+func (s *authShim) Clone() Authenticator {
+	return &noAuth{}
+}
+
+// String toString
+func (s *authShim) String() string {
+	return "AuthShim"
+}
+
+// Authorize authorizes the current request with the top most Authorizer
+func (n *negoAuth) Authorize(c *http.Client, rq *http.Request, path string) error {
+	if len(n.auths) == 0 {
+		return NewPathError("NoAuthenticator", path, 400)
+	}
+	return n.auths[0].Authorize(c, rq, path)
+}
+
+// Verify verifies the authentication and selects the next one based on the result
+func (n *negoAuth) Verify(c *http.Client, rs *http.Response, path string) (redo bool, err error) {
+	if len(n.auths) == 0 {
+		return false, NewPathError("NoAuthenticator", path, 400)
+	}
+	redo, err = n.auths[0].Verify(c, rs, path)
+	if err != nil {
+		if len(n.auths) > 1 {
+			n.auths[0].Close()
+			n.auths = n.auths[1:]
+			return true, nil
+		}
+	} else if redo {
+		return
+	} else {
+		auth := n.auths[0]
+		n.auths = n.auths[1:]
+		n.setDefaultAuthenticator(auth)
+		return
+	}
+
+	return false, NewPathError("NoAuthenticator", path, rs.StatusCode)
+}
+
+// Close will close the underlying authenticators.
+func (n *negoAuth) Close() error {
+	for _, a := range n.auths {
+		a.Close()
+	}
+	n.setDefaultAuthenticator = nil
+	return nil
+}
+
+// Clone clones the underlying authenticators.
+func (n *negoAuth) Clone() Authenticator {
+	auths := make([]Authenticator, len(n.auths))
+	for i, e := range n.auths {
+		auths[i] = e.Clone()
+	}
+	return &negoAuth{auths: auths, setDefaultAuthenticator: n.setDefaultAuthenticator}
+}
+
+func (n *negoAuth) String() string {
+	return "NegoAuth"
+}
+
+// Authorize the current request
+func (n *noAuth) Authorize(c *http.Client, rq *http.Request, path string) error {
+	return nil
+}
+
+// Verify checks for authentication issues and may trigger a re-authentication
+func (n *noAuth) Verify(c *http.Client, rs *http.Response, path string) (redo bool, err error) {
+	if "" != rs.Header.Get("Www-Authenticate") {
+		err = ErrAuthChanged
+	}
+	return
+}
+
+// Close closes all resources
+func (n *noAuth) Close() error {
+	return nil
+}
+
+// Clone creates a copy of itself
+func (n *noAuth) Clone() Authenticator {
+	// no copy due to read only access
+	return n
+}
+
+// String toString
+func (n *noAuth) String() string {
+	return "NoAuth"
+}
+
+// Authorize the current request
+func (n *nullAuth) Authorize(c *http.Client, rq *http.Request, path string) error {
+	rq.Header.Set(XInhibitRedirect, "1")
+	return nil
+}
+
+// Verify checks for authentication issues and may trigger a re-authentication
+func (n *nullAuth) Verify(c *http.Client, rs *http.Response, path string) (redo bool, err error) {
+	return true, ErrAuthChanged
+}
+
+// Close closes all resources
+func (n *nullAuth) Close() error {
+	return nil
+}
+
+// Clone creates a copy of itself
+func (n *nullAuth) Clone() Authenticator {
+	// no copy due to read only access
+	return n
+}
+
+// String toString
+func (n *nullAuth) String() string {
+	return "NullAuth"
+}
+
+// NewAuthenticator creates an Authenticator (Shim) per request
+func (b *preemptiveAuthorizer) NewAuthenticator(body io.Reader) (Authenticator, io.Reader) {
+	return b.auth.Clone(), body
+}
+
+// AddAuthenticator Will PANIC because it may only have a single authentication method
+func (b *preemptiveAuthorizer) AddAuthenticator(key string, fn AuthFactory) {
+	panic("You're funny! A preemptive authorizer may only have a single authentication method")
+}
--- a/auth_test.go
+++ b/auth_test.go
@ -0,0 +1,62 @@
+package gowebdav
+
+import (
+	"bytes"
+	"net/http"
+	"strings"
+	"testing"
+)
+
+func TestEmptyAuth(t *testing.T) {
+	auth := NewEmptyAuth()
+	srv, _, _ := newAuthSrv(t, basicAuth)
+	defer srv.Close()
+	cli := NewAuthClient(srv.URL, auth)
+	if err := cli.Connect(); err == nil {
+		t.Fatalf("got nil want error")
+	}
+}
+
+func TestRedirectAuthWIP(t *testing.T) {
+	hasPassedAuthServer := false
+	authHandler := func(h http.Handler) http.HandlerFunc {
+		return func(w http.ResponseWriter, r *http.Request) {
+			if user, passwd, ok := r.BasicAuth(); ok {
+				if user == "user" && passwd == "password" {
+					hasPassedAuthServer = true
+					w.WriteHeader(200)
+					return
+				}
+			}
+			w.Header().Set("Www-Authenticate", `Basic realm="x"`)
+			w.WriteHeader(401)
+		}
+	}
+
+	psrv, _, _ := newAuthSrv(t, authHandler)
+	defer psrv.Close()
+
+	dataHandler := func(h http.Handler) http.HandlerFunc {
+		return func(w http.ResponseWriter, r *http.Request) {
+			hasAuth := strings.Contains(r.Header.Get("Authorization"), "Basic dXNlcjpwYXNzd29yZA==")
+
+			if hasPassedAuthServer && hasAuth {
+				h.ServeHTTP(w, r)
+				return
+			}
+			w.Header().Set("Www-Authenticate", `Basic realm="x"`)
+			http.Redirect(w, r, psrv.URL+"/", 302)
+		}
+	}
+
+	srv, _, _ := newAuthSrv(t, dataHandler)
+	defer srv.Close()
+	cli := NewClient(srv.URL, "user", "password")
+	data, err := cli.Read("/hello.txt")
+	if err != nil {
+		t.Logf("WIP got error=%v; want nil", err)
+	}
+	if bytes.Compare(data, []byte("hello gowebdav\n")) != 0 {
+		t.Logf("WIP got data=%v; want=hello gowebdav", data)
+	}
+}
--- a/basicAuth.go
+++ b/basicAuth.go
@ -1,7 +1,7 @@
 package gowebdav

 import (
-	"encoding/base64"
+	"fmt"
 	"net/http"
 )

@ -11,24 +11,37 @@ type BasicAuth struct {
 	pw   string
 }

-// Type identifies the BasicAuthenticator
-func (b *BasicAuth) Type() string {
-	return "BasicAuth"
-}
-
-// User holds the BasicAuth username
-func (b *BasicAuth) User() string {
-	return b.user
-}
-
-// Pass holds the BasicAuth password
-func (b *BasicAuth) Pass() string {
-	return b.pw
+// NewDigestAuth creates a new instance of our Digest Authenticator
+func NewBasicAuth(login, secret string) (Authenticator, error) {
+	return &BasicAuth{user: login, pw: secret}, nil
 }

 // Authorize the current request
-func (b *BasicAuth) Authorize(req *http.Request, method string, path string) {
-	a := b.user + ":" + b.pw
-	auth := "Basic " + base64.StdEncoding.EncodeToString([]byte(a))
-	req.Header.Set("Authorization", auth)
+func (b *BasicAuth) Authorize(c *http.Client, rq *http.Request, path string) error {
+	rq.SetBasicAuth(b.user, b.pw)
+	return nil
+}
+
+// Verify verifies if the authentication
+func (b *BasicAuth) Verify(c *http.Client, rs *http.Response, path string) (redo bool, err error) {
+	if rs.StatusCode == 401 {
+		err = NewPathError("Authorize", path, rs.StatusCode)
+	}
+	return
+}
+
+// Close cleans up all resources
+func (b *BasicAuth) Close() error {
+	return nil
+}
+
+// Clone creates a Copy of itself
+func (b *BasicAuth) Clone() Authenticator {
+	// no copy due to read only access
+	return b
+}
+
+// String toString
+func (b *BasicAuth) String() string {
+	return fmt.Sprintf("BasicAuth login: %s", b.user)
 }
--- a/basicAuth_test.go
+++ b/basicAuth_test.go
@ -0,0 +1,51 @@
+package gowebdav
+
+import (
+	"net/http"
+	"testing"
+)
+
+func TestNewBasicAuth(t *testing.T) {
+	a := &BasicAuth{user: "user", pw: "password"}
+
+	ex := "BasicAuth login: user"
+	if a.String() != ex {
+		t.Error("expected: " + ex + " got: " + a.String())
+	}
+
+	if a.Clone() != a {
+		t.Error("expected the same instance")
+	}
+
+	if a.Close() != nil {
+		t.Error("expected close without errors")
+	}
+}
+
+func TestBasicAuthAuthorize(t *testing.T) {
+	a := &BasicAuth{user: "user", pw: "password"}
+	rq, _ := http.NewRequest("GET", "http://localhost/", nil)
+	a.Authorize(nil, rq, "/")
+	if rq.Header.Get("Authorization") != "Basic dXNlcjpwYXNzd29yZA==" {
+		t.Error("got wrong Authorization header: " + rq.Header.Get("Authorization"))
+	}
+}
+
+func TestPreemtiveBasicAuth(t *testing.T) {
+	a := &BasicAuth{user: "user", pw: "password"}
+	auth := NewPreemptiveAuth(a)
+	n, b := auth.NewAuthenticator(nil)
+	if b != nil {
+		t.Error("expected body to be nil")
+	}
+	if n != a {
+		t.Error("expected the same instance")
+	}
+
+	srv, _, _ := newAuthSrv(t, basicAuth)
+	defer srv.Close()
+	cli := NewAuthClient(srv.URL, auth)
+	if err := cli.Connect(); err != nil {
+		t.Fatalf("got error: %v, want nil", err)
+	}
+}
--- a/client.go
+++ b/client.go
@ -10,57 +10,39 @@ import (
 	"os"
 	pathpkg "path"
 	"strings"
-	"sync"
 	"time"
 )

+const XInhibitRedirect = "X-Gowebdav-Inhibit-Redirect"
+
 // Client defines our structure
 type Client struct {
 	root        string
 	headers     http.Header
 	interceptor func(method string, rq *http.Request)
 	c           *http.Client
-
-	authMutex sync.Mutex
-	auth      Authenticator
-}
-
-// Authenticator stub
-type Authenticator interface {
-	Type() string
-	User() string
-	Pass() string
-	Authorize(*http.Request, string, string)
-}
-
-// NoAuth structure holds our credentials
-type NoAuth struct {
-	user string
-	pw   string
-}
-
-// Type identifies the authenticator
-func (n *NoAuth) Type() string {
-	return "NoAuth"
-}
-
-// User returns the current user
-func (n *NoAuth) User() string {
-	return n.user
-}
-
-// Pass returns the current password
-func (n *NoAuth) Pass() string {
-	return n.pw
-}
-
-// Authorize the current request
-func (n *NoAuth) Authorize(req *http.Request, method string, path string) {
+	auth        Authorizer
 }

 // NewClient creates a new instance of client
 func NewClient(uri, user, pw string) *Client {
-	return &Client{FixSlash(uri), make(http.Header), nil, &http.Client{}, sync.Mutex{}, &NoAuth{user, pw}}
+	return NewAuthClient(uri, NewAutoAuth(user, pw))
+}
+
+// NewAuthClient creates a new client instance with a custom Authorizer
+func NewAuthClient(uri string, auth Authorizer) *Client {
+	c := &http.Client{
+		CheckRedirect: func(rq *http.Request, via []*http.Request) error {
+			if len(via) >= 10 {
+				return ErrTooManyRedirects
+			}
+			if via[0].Header.Get(XInhibitRedirect) != "" {
+				return http.ErrUseLastResponse
+			}
+			return nil
+		},
+	}
+	return &Client{root: FixSlash(uri), headers: make(http.Header), interceptor: nil, c: c, auth: auth}
 }

 // SetHeader lets us set arbitrary headers for a given client
@ -83,6 +65,11 @@ func (c *Client) SetTransport(transport http.RoundTripper) {
 	c.c.Transport = transport
 }

+// SetJar exposes the ability to set a cookie jar to the client.
+func (c *Client) SetJar(jar http.CookieJar) {
+	c.c.Jar = jar
+}
+
 // Connect connects to our dav server
 func (c *Client) Connect() error {
 	rs, err := c.options("/")
@ -96,7 +83,7 @@ func (c *Client) Connect() error {
 	}

 	if rs.StatusCode != 200 {
-		return newPathError("Connect", c.root, rs.StatusCode)
+		return NewPathError("Connect", c.root, rs.StatusCode)
 	}

 	return nil
@ -140,7 +127,7 @@ func (c *Client) ReadDir(path string) ([]os.FileInfo, error) {
 				r.Props = nil
 				return nil
 			}
-			return newPathError("ReadDir", path, 405)
+			return NewPathError("ReadDir", path, 405)
 		}

 		if p := getProps(r, "200"); p != nil {
@ -187,7 +174,7 @@ func (c *Client) ReadDir(path string) ([]os.FileInfo, error) {

 	if err != nil {
 		if _, ok := err.(*os.PathError); !ok {
-			err = newPathErrorErr("ReadDir", path, err)
+			err = NewPathErrorErr("ReadDir", path, err)
 		}
 	}
 	return files, err
@ -210,7 +197,7 @@ func (c *Client) Stat(path string) (os.FileInfo, error) {
 					f.path += "/"
 				}
 				f.size = 0
-				f.modified = time.Unix(0, 0)
+				f.modified = parseModified(&p.Modified)
 				f.isdir = true
 			} else {
 				f.size = parseInt64(&p.Size)
@ -239,7 +226,7 @@ func (c *Client) Stat(path string) (os.FileInfo, error) {

 	if err != nil {
 		if _, ok := err.(*os.PathError); !ok {
-			err = newPathErrorErr("ReadDir", path, err)
+			err = NewPathErrorErr("ReadDir", path, err)
 		}
 	}
 	return f, err
@ -254,7 +241,7 @@ func (c *Client) Remove(path string) error {
 func (c *Client) RemoveAll(path string) error {
 	rs, err := c.req("DELETE", path, nil, nil)
 	if err != nil {
-		return newPathError("Remove", path, 400)
+		return NewPathError("Remove", path, 400)
 	}
 	err = rs.Body.Close()
 	if err != nil {
@ -265,7 +252,7 @@ func (c *Client) RemoveAll(path string) error {
 		return nil
 	}

-	return newPathError("Remove", path, rs.StatusCode)
+	return NewPathError("Remove", path, rs.StatusCode)
 }

 // Mkdir makes a directory
@ -279,7 +266,7 @@ func (c *Client) Mkdir(path string, _ os.FileMode) (err error) {
 		return nil
 	}

-	return newPathError("Mkdir", path, status)
+	return NewPathError("Mkdir", path, status)
 }

 // MkdirAll like mkdir -p, but for webdav
@ -305,13 +292,13 @@ func (c *Client) MkdirAll(path string, _ os.FileMode) (err error) {
 				return
 			}
 			if status != 201 {
-				return newPathError("MkdirAll", sub, status)
+				return NewPathError("MkdirAll", sub, status)
 			}
 		}
 		return nil
 	}

-	return newPathError("MkdirAll", path, status)
+	return NewPathError("MkdirAll", path, status)
 }

 // Rename moves a file from A to B
@ -346,7 +333,7 @@ func (c *Client) Read(path string) ([]byte, error) {
 func (c *Client) ReadStream(path string) (io.ReadCloser, error) {
 	rs, err := c.req("GET", path, nil, nil)
 	if err != nil {
-		return nil, newPathErrorErr("ReadStream", path, err)
+		return nil, NewPathErrorErr("ReadStream", path, err)
 	}

 	if rs.StatusCode == 200 {
@ -354,7 +341,7 @@ func (c *Client) ReadStream(path string) (io.ReadCloser, error) {
 	}

 	rs.Body.Close()
-	return nil, newPathError("ReadStream", path, rs.StatusCode)
+	return nil, NewPathError("ReadStream", path, rs.StatusCode)
 }

 // ReadStreamRange reads the stream representing a subset of bytes for a given path,
@ -374,7 +361,7 @@ func (c *Client) ReadStreamRange(path string, offset, length int64) (io.ReadClos
 		}
 	})
 	if err != nil {
-		return nil, newPathErrorErr("ReadStreamRange", path, err)
+		return nil, NewPathErrorErr("ReadStreamRange", path, err)
 	}

 	if rs.StatusCode == http.StatusPartialContent {
@ -387,15 +374,15 @@ func (c *Client) ReadStreamRange(path string, offset, length int64) (io.ReadClos
 	if rs.StatusCode == 200 {
 		// discard first 'offset' bytes.
 		if _, err := io.Copy(io.Discard, io.LimitReader(rs.Body, offset)); err != nil {
-			return nil, newPathErrorErr("ReadStreamRange", path, err)
+			return nil, NewPathErrorErr("ReadStreamRange", path, err)
 		}

 		// return a io.ReadCloser that is limited to `length` bytes.
-		return &limitedReadCloser{rs.Body, int(length)}, nil
+		return &limitedReadCloser{rc: rs.Body, remaining: int(length)}, nil
 	}

 	rs.Body.Close()
-	return nil, newPathError("ReadStream", path, rs.StatusCode)
+	return nil, NewPathError("ReadStream", path, rs.StatusCode)
 }

 // Write writes data to a given path
@ -425,7 +412,7 @@ func (c *Client) Write(path string, data []byte, _ os.FileMode) (err error) {
 		}
 	}

-	return newPathError("Write", path, s)
+	return NewPathError("Write", path, s)
 }

 // WriteStream writes a stream
@ -446,6 +433,6 @@ func (c *Client) WriteStream(path string, stream io.Reader, _ os.FileMode) (err
 		return nil

 	default:
-		return newPathError("WriteStream", path, s)
+		return NewPathError("WriteStream", path, s)
 	}
 }
--- a/client_test.go
+++ b/client_test.go
@ -17,6 +17,12 @@ import (
 	"golang.org/x/net/webdav"
 )

+func noAuthHndl(h http.Handler) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		h.ServeHTTP(w, r)
+	}
+}
+
 func basicAuth(h http.Handler) http.HandlerFunc {
 	return func(w http.ResponseWriter, r *http.Request) {
 		if user, passwd, ok := r.BasicAuth(); ok {
@ -33,6 +39,54 @@ func basicAuth(h http.Handler) http.HandlerFunc {
 	}
 }

+func multipleAuth(h http.Handler) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		notAuthed := false
+		if r.Header.Get("Authorization") == "" {
+			notAuthed = true
+		} else if user, passwd, ok := r.BasicAuth(); ok {
+			if user == "user" && passwd == "password" {
+				h.ServeHTTP(w, r)
+				return
+			}
+			notAuthed = true
+		} else if strings.HasPrefix(r.Header.Get("Authorization"), "Digest ") {
+			pairs := strings.TrimPrefix(r.Header.Get("Authorization"), "Digest ")
+			digestParts := make(map[string]string)
+			for _, pair := range strings.Split(pairs, ",") {
+				kv := strings.SplitN(strings.TrimSpace(pair), "=", 2)
+				key, value := kv[0], kv[1]
+				value = strings.Trim(value, `"`)
+				digestParts[key] = value
+			}
+			if digestParts["qop"] == "" {
+				digestParts["qop"] = "auth"
+			}
+
+			ha1 := getMD5(fmt.Sprint(digestParts["username"], ":", digestParts["realm"], ":", "digestPW"))
+			ha2 := getMD5(fmt.Sprint(r.Method, ":", digestParts["uri"]))
+			expected := getMD5(fmt.Sprint(ha1,
+				":", digestParts["nonce"],
+				":", digestParts["nc"],
+				":", digestParts["cnonce"],
+				":", digestParts["qop"],
+				":", ha2))
+
+			if expected == digestParts["response"] {
+				h.ServeHTTP(w, r)
+				return
+			}
+			notAuthed = true
+		}
+
+		if notAuthed {
+			w.Header().Add("WWW-Authenticate", `Digest realm="testrealm@host.com", qop="auth,auth-int",nonce="dcd98b7102dd2f0e8b11d0f600bfb0c093",opaque="5ccc069c403ebaf9f0171e9517f40e41"`)
+			w.Header().Add("WWW-Authenticate", `Basic realm="x"`)
+			w.WriteHeader(401)
+		}
+	}
+}
+
 func fillFs(t *testing.T, fs webdav.FileSystem) context.Context {
 	ctx := context.Background()
 	f, err := fs.OpenFile(ctx, "hello.txt", os.O_CREATE, 0644)
@ -55,18 +109,27 @@ func fillFs(t *testing.T, fs webdav.FileSystem) context.Context {
 }

 func newServer(t *testing.T) (*Client, *httptest.Server, webdav.FileSystem, context.Context) {
-	mux := http.NewServeMux()
-	fs := webdav.NewMemFS()
-	ctx := fillFs(t, fs)
-	mux.HandleFunc("/", basicAuth(&webdav.Handler{
-		FileSystem: fs,
-		LockSystem: webdav.NewMemLS(),
-	}))
-	srv := httptest.NewServer(mux)
+	return newAuthServer(t, basicAuth)
+}
+
+func newAuthServer(t *testing.T, auth func(h http.Handler) http.HandlerFunc) (*Client, *httptest.Server, webdav.FileSystem, context.Context) {
+	srv, fs, ctx := newAuthSrv(t, auth)
 	cli := NewClient(srv.URL, "user", "password")
 	return cli, srv, fs, ctx
 }

+func newAuthSrv(t *testing.T, auth func(h http.Handler) http.HandlerFunc) (*httptest.Server, webdav.FileSystem, context.Context) {
+	mux := http.NewServeMux()
+	fs := webdav.NewMemFS()
+	ctx := fillFs(t, fs)
+	mux.HandleFunc("/", auth(&webdav.Handler{
+		FileSystem: fs,
+		LockSystem: webdav.NewMemLS(),
+	}))
+	srv := httptest.NewServer(mux)
+	return srv, fs, ctx
+}
+
 func TestConnect(t *testing.T) {
 	cli, srv, _, _ := newServer(t)
 	defer srv.Close()
@ -80,6 +143,54 @@ func TestConnect(t *testing.T) {
 	}
 }

+func TestConnectMultipleAuth(t *testing.T) {
+	cli, srv, _, _ := newAuthServer(t, multipleAuth)
+	defer srv.Close()
+	if err := cli.Connect(); err != nil {
+		t.Fatalf("got error: %v, want nil", err)
+	}
+
+	cli = NewClient(srv.URL, "digestUser", "digestPW")
+	if err := cli.Connect(); err != nil {
+		t.Fatalf("got nil, want error: %v", err)
+	}
+
+	cli = NewClient(srv.URL, "no", "no")
+	if err := cli.Connect(); err == nil {
+		t.Fatalf("got nil, want error: %v", err)
+	}
+}
+
+func TestConnectMultiAuthII(t *testing.T) {
+	cli, srv, _, _ := newAuthServer(t, func(h http.Handler) http.HandlerFunc {
+		return func(w http.ResponseWriter, r *http.Request) {
+			if user, passwd, ok := r.BasicAuth(); ok {
+				if user == "user" && passwd == "password" {
+					h.ServeHTTP(w, r)
+					return
+				}
+
+				http.Error(w, "not authorized", 403)
+			} else {
+				w.Header().Add("WWW-Authenticate", `FooAuth`)
+				w.Header().Add("WWW-Authenticate", `BazAuth`)
+				w.Header().Add("WWW-Authenticate", `BarAuth`)
+				w.Header().Add("WWW-Authenticate", `Basic realm="x"`)
+				w.WriteHeader(401)
+			}
+		}
+	})
+	defer srv.Close()
+	if err := cli.Connect(); err != nil {
+		t.Fatalf("got error: %v, want nil", err)
+	}
+
+	cli = NewClient(srv.URL, "no", "no")
+	if err := cli.Connect(); err == nil {
+		t.Fatalf("got nil, want error: %v", err)
+	}
+}
+
 func TestReadDirConcurrent(t *testing.T) {
 	cli, srv, _, _ := newServer(t)
 	defer srv.Close()
@ -135,6 +246,24 @@ func TestRead(t *testing.T) {
 	}
 }

+func TestReadNoAuth(t *testing.T) {
+	cli, srv, _, _ := newAuthServer(t, noAuthHndl)
+	defer srv.Close()
+
+	data, err := cli.Read("/hello.txt")
+	if err != nil || bytes.Compare(data, []byte("hello gowebdav\n")) != 0 {
+		t.Fatalf("got: %v, want data: %s", err, []byte("hello gowebdav\n"))
+	}
+
+	data, err = cli.Read("/404.txt")
+	if err == nil {
+		t.Fatalf("got: %v, want error: %v", data, err)
+	}
+	if !IsErrNotFound(err) {
+		t.Fatalf("got: %v, want 404 error", err)
+	}
+}
+
 func TestReadStream(t *testing.T) {
 	cli, srv, _, _ := newServer(t)
 	defer srv.Close()
--- a/cmd/gowebdav/main.go
+++ b/cmd/gowebdav/main.go
@ -13,7 +13,7 @@ import (
 	"runtime"
 	"strings"

-	d "github.com/studio-b12/gowebdav"
+	d "git.siteop.biz/shoopea/gowebdav"
 )

 func main() {
@ -55,6 +55,10 @@ func main() {

 	c := d.NewClient(*root, *user, *password)

+	if e := c.Connect(); e != nil {
+		panic(e)
+	}
+
 	cmd := getCmd(*method)

 	if e := cmd(c, flag.Arg(0), flag.Arg(1)); e != nil {
--- a/digestAuth.go
+++ b/digestAuth.go
@ -17,28 +17,46 @@ type DigestAuth struct {
 	digestParts map[string]string
 }

-// Type identifies the DigestAuthenticator
-func (d *DigestAuth) Type() string {
-	return "DigestAuth"
-}
-
-// User holds the DigestAuth username
-func (d *DigestAuth) User() string {
-	return d.user
-}
-
-// Pass holds the DigestAuth password
-func (d *DigestAuth) Pass() string {
-	return d.pw
+// NewDigestAuth creates a new instance of our Digest Authenticator
+func NewDigestAuth(login, secret string, rs *http.Response) (Authenticator, error) {
+	return &DigestAuth{user: login, pw: secret, digestParts: digestParts(rs)}, nil
 }

 // Authorize the current request
-func (d *DigestAuth) Authorize(req *http.Request, method string, path string) {
+func (d *DigestAuth) Authorize(c *http.Client, rq *http.Request, path string) error {
 	d.digestParts["uri"] = path
-	d.digestParts["method"] = method
+	d.digestParts["method"] = rq.Method
 	d.digestParts["username"] = d.user
 	d.digestParts["password"] = d.pw
-	req.Header.Set("Authorization", getDigestAuthorization(d.digestParts))
+	rq.Header.Set("Authorization", getDigestAuthorization(d.digestParts))
+	return nil
+}
+
+// Verify checks for authentication issues and may trigger a re-authentication
+func (d *DigestAuth) Verify(c *http.Client, rs *http.Response, path string) (redo bool, err error) {
+	if rs.StatusCode == 401 {
+		err = NewPathError("Authorize", path, rs.StatusCode)
+	}
+	return
+}
+
+// Close cleans up all resources
+func (d *DigestAuth) Close() error {
+	return nil
+}
+
+// Clone creates a copy of itself
+func (d *DigestAuth) Clone() Authenticator {
+	parts := make(map[string]string, len(d.digestParts))
+	for k, v := range d.digestParts {
+		parts[k] = v
+	}
+	return &DigestAuth{user: d.user, pw: d.pw, digestParts: parts}
+}
+
+// String toString
+func (d *DigestAuth) String() string {
+	return fmt.Sprintf("DigestAuth login: %s", d.user)
 }

 func digestParts(resp *http.Response) map[string]string {
--- a/digestAuth_test.go
+++ b/digestAuth_test.go
@ -0,0 +1,35 @@
+package gowebdav
+
+import (
+	"net/http"
+	"strings"
+	"testing"
+)
+
+func TestNewDigestAuth(t *testing.T) {
+	a := &DigestAuth{user: "user", pw: "password", digestParts: make(map[string]string, 0)}
+
+	ex := "DigestAuth login: user"
+	if a.String() != ex {
+		t.Error("expected: " + ex + " got: " + a.String())
+	}
+
+	if a.Clone() == a {
+		t.Error("expected a different instance")
+	}
+
+	if a.Close() != nil {
+		t.Error("expected close without errors")
+	}
+}
+
+func TestDigestAuthAuthorize(t *testing.T) {
+	a := &DigestAuth{user: "user", pw: "password", digestParts: make(map[string]string, 0)}
+	rq, _ := http.NewRequest("GET", "http://localhost/", nil)
+	a.Authorize(nil, rq, "/")
+	// TODO this is a very lazy test it cuts of cnonce
+	ex := `Digest username="user", realm="", nonce="", uri="/", nc=1, cnonce="`
+	if strings.Index(rq.Header.Get("Authorization"), ex) != 0 {
+		t.Error("got wrong Authorization header: " + rq.Header.Get("Authorization"))
+	}
+}
--- a/errors.go
+++ b/errors.go
@ -1,10 +1,18 @@
 package gowebdav

 import (
+	"errors"
 	"fmt"
 	"os"
 )

+// ErrAuthChanged must be returned from the Verify method as an error
+// to trigger a re-authentication / negotiation with a new authenticator.
+var ErrAuthChanged = errors.New("authentication failed, change algorithm")
+
+// ErrTooManyRedirects will be used as return error if a request exceeds 10 redirects.
+var ErrTooManyRedirects = errors.New("stopped after 10 redirects")
+
 // StatusError implements error and wraps
 // an erroneous status code.
 type StatusError struct {
@ -32,7 +40,7 @@ func IsErrNotFound(err error) bool {
 	return IsErrCode(err, 404)
 }

-func newPathError(op string, path string, statusCode int) error {
+func NewPathError(op string, path string, statusCode int) error {
 	return &os.PathError{
 		Op:   op,
 		Path: path,
@ -40,7 +48,7 @@ func newPathError(op string, path string, statusCode int) error {
 	}
 }

-func newPathErrorErr(op string, path string, err error) error {
+func NewPathErrorErr(op string, path string, err error) error {
 	return &os.PathError{
 		Op:   op,
 		Path: path,
--- a/go.mod
+++ b/go.mod
@ -1,3 +1,3 @@
-module github.com/studio-b12/gowebdav
+module git.siteop.biz/shoopea/gowebdav

 go 1.17
--- a/passportAuth.go
+++ b/passportAuth.go
@ -0,0 +1,181 @@
+package gowebdav
+
+import (
+	"fmt"
+	"io"
+	"net/http"
+	"net/url"
+	"strings"
+)
+
+// PassportAuth structure holds our credentials
+type PassportAuth struct {
+	user            string
+	pw              string
+	cookies         []http.Cookie
+	inhibitRedirect bool
+}
+
+// constructor for PassportAuth creates a new PassportAuth object and
+// automatically authenticates against the given partnerURL
+func NewPassportAuth(c *http.Client, user, pw, partnerURL string, header *http.Header) (Authenticator, error) {
+	p := &PassportAuth{
+		user:            user,
+		pw:              pw,
+		inhibitRedirect: true,
+	}
+	err := p.genCookies(c, partnerURL, header)
+	return p, err
+}
+
+// Authorize the current request
+func (p *PassportAuth) Authorize(c *http.Client, rq *http.Request, path string) error {
+	// prevent redirects to detect subsequent authentication requests
+	if p.inhibitRedirect {
+		rq.Header.Set(XInhibitRedirect, "1")
+	} else {
+		p.inhibitRedirect = true
+	}
+	for _, cookie := range p.cookies {
+		rq.AddCookie(&cookie)
+	}
+	return nil
+}
+
+// Verify verifies if the authentication is good
+func (p *PassportAuth) Verify(c *http.Client, rs *http.Response, path string) (redo bool, err error) {
+	switch rs.StatusCode {
+	case 301, 302, 307, 308:
+		redo = true
+		if rs.Header.Get("Www-Authenticate") != "" {
+			// re-authentication required as we are redirected to the login page
+			err = p.genCookies(c, rs.Request.URL.String(), &rs.Header)
+		} else {
+			// just a redirect, follow it
+			p.inhibitRedirect = false
+		}
+	case 401:
+		err = NewPathError("Authorize", path, rs.StatusCode)
+	}
+	return
+}
+
+// Close cleans up all resources
+func (p *PassportAuth) Close() error {
+	return nil
+}
+
+// Clone creates a Copy of itself
+func (p *PassportAuth) Clone() Authenticator {
+	// create a copy to allow independent cookie updates
+	clonedCookies := make([]http.Cookie, len(p.cookies))
+	copy(clonedCookies, p.cookies)
+
+	return &PassportAuth{
+		user:            p.user,
+		pw:              p.pw,
+		cookies:         clonedCookies,
+		inhibitRedirect: true,
+	}
+}
+
+// String toString
+func (p *PassportAuth) String() string {
+	return fmt.Sprintf("PassportAuth login: %s", p.user)
+}
+
+func (p *PassportAuth) genCookies(c *http.Client, partnerUrl string, header *http.Header) error {
+	// For more details refer to:
+	// https://learn.microsoft.com/en-us/openspecs/windows_protocols/ms-pass/2c80637d-438c-4d4b-adc5-903170a779f3
+	// Skipping step 1 and 2 as we already have the partner server challenge
+
+	baseAuthenticationServer := header.Get("Location")
+	baseAuthenticationServerURL, err := url.Parse(baseAuthenticationServer)
+	if err != nil {
+		return err
+	}
+
+	// Skipping step 3 and 4 as we already know that we need and have the user's credentials
+	// Step 5 (Sign-in request)
+	authenticationServerUrl := url.URL{
+		Scheme: baseAuthenticationServerURL.Scheme,
+		Host:   baseAuthenticationServerURL.Host,
+		Path:   "/login2.srf",
+	}
+
+	partnerServerChallenge := strings.Split(header.Get("Www-Authenticate"), " ")[1]
+
+	req := http.Request{
+		Method: "GET",
+		URL:    &authenticationServerUrl,
+		Header: http.Header{
+			"Authorization": []string{"Passport1.4 sign-in=" + url.QueryEscape(p.user) + ",pwd=" + url.QueryEscape(p.pw) + ",OrgVerb=GET,OrgUrl=" + partnerUrl + "," + partnerServerChallenge},
+		},
+	}
+
+	rs, err := c.Do(&req)
+	if err != nil {
+		return err
+	}
+	io.Copy(io.Discard, rs.Body)
+	rs.Body.Close()
+	if rs.StatusCode != 200 {
+		return NewPathError("Authorize", "/", rs.StatusCode)
+	}
+
+	// Step 6 (Token Response from Authentication Server)
+	tokenResponseHeader := rs.Header.Get("Authentication-Info")
+	if tokenResponseHeader == "" {
+		return NewPathError("Authorize", "/", 401)
+	}
+	tokenResponseHeaderList := strings.Split(tokenResponseHeader, ",")
+	token := ""
+	for _, tokenResponseHeader := range tokenResponseHeaderList {
+		if strings.HasPrefix(tokenResponseHeader, "from-PP='") {
+			token = tokenResponseHeader
+			break
+		}
+	}
+	if token == "" {
+		return NewPathError("Authorize", "/", 401)
+	}
+
+	// Step 7 (First Authentication Request to Partner Server)
+	origUrl, err := url.Parse(partnerUrl)
+	if err != nil {
+		return err
+	}
+	req = http.Request{
+		Method: "GET",
+		URL:    origUrl,
+		Header: http.Header{
+			"Authorization": []string{"Passport1.4 " + token},
+		},
+	}
+
+	rs, err = c.Do(&req)
+	if err != nil {
+		return err
+	}
+	io.Copy(io.Discard, rs.Body)
+	rs.Body.Close()
+	if rs.StatusCode != 200 && rs.StatusCode != 302 {
+		return NewPathError("Authorize", "/", rs.StatusCode)
+	}
+
+	// Step 8 (Set Token Message from Partner Server)
+	cookies := rs.Header.Values("Set-Cookie")
+	p.cookies = make([]http.Cookie, len(cookies))
+	for i, cookie := range cookies {
+		cookieParts := strings.Split(cookie, ";")
+		cookieName := strings.Split(cookieParts[0], "=")[0]
+		cookieValue := strings.Split(cookieParts[0], "=")[1]
+
+		p.cookies[i] = http.Cookie{
+			Name:  cookieName,
+			Value: cookieValue,
+		}
+	}
+
+	return nil
+}
--- a/passportAuth_test.go
+++ b/passportAuth_test.go
@ -0,0 +1,66 @@
+package gowebdav
+
+import (
+	"bytes"
+	"net/http"
+	"net/url"
+	"regexp"
+	"testing"
+)
+
+// testing the creation is enough as it handles the authorization during init
+func TestNewPassportAuth(t *testing.T) {
+	user := "user"
+	pass := "password"
+	p1 := "some,comma,separated,values"
+	token := "from-PP='token'"
+
+	authHandler := func(h http.Handler) http.HandlerFunc {
+		return func(w http.ResponseWriter, r *http.Request) {
+			reg, err := regexp.Compile("Passport1\\.4 sign-in=" + url.QueryEscape(user) + ",pwd=" + url.QueryEscape(pass) + ",OrgVerb=GET,OrgUrl=.*," + p1)
+			if err != nil {
+				t.Error(err)
+			}
+			if reg.MatchString(r.Header.Get("Authorization")) {
+				w.Header().Set("Authentication-Info", token)
+				w.WriteHeader(200)
+				return
+			}
+		}
+	}
+	authsrv, _, _ := newAuthSrv(t, authHandler)
+	defer authsrv.Close()
+
+	dataHandler := func(h http.Handler) http.HandlerFunc {
+		return func(w http.ResponseWriter, r *http.Request) {
+			reg, err := regexp.Compile("Passport1\\.4 " + token)
+			if err != nil {
+				t.Error(err)
+			}
+			if reg.MatchString(r.Header.Get("Authorization")) {
+				w.Header().Set("Set-Cookie", "Pass=port")
+				h.ServeHTTP(w, r)
+				return
+			}
+			for _, c := range r.Cookies() {
+				if c.Name == "Pass" && c.Value == "port" {
+					h.ServeHTTP(w, r)
+					return
+				}
+			}
+			w.Header().Set("Www-Authenticate", "Passport1.4 "+p1)
+			http.Redirect(w, r, authsrv.URL+"/", 302)
+		}
+	}
+	srv, _, _ := newAuthSrv(t, dataHandler)
+	defer srv.Close()
+
+	cli := NewClient(srv.URL, user, pass)
+	data, err := cli.Read("/hello.txt")
+	if err != nil {
+		t.Errorf("got error=%v; want nil", err)
+	}
+	if !bytes.Equal(data, []byte("hello gowebdav\n")) {
+		t.Logf("got data=%v; want=hello gowebdav", data)
+	}
+}
--- a/requests.go
+++ b/requests.go
@ -1,7 +1,6 @@
 package gowebdav

 import (
-	"bytes"
 	"io"
 	"log"
 	"net/http"
@ -9,83 +8,52 @@ import (
 	"strings"
 )

-func (c *Client) req(method, path string, body io.Reader, intercept func(*http.Request)) (req *http.Response, err error) {
+func (c *Client) req(method, path string, body io.Reader, intercept func(*http.Request)) (rs *http.Response, err error) {
+	var redo bool
 	var r *http.Request
-	var retryBuf io.Reader
+	var uri = PathEscape(Join(c.root, path))
+	auth, body := c.auth.NewAuthenticator(body)
+	defer auth.Close()

-	if body != nil {
-		// If the authorization fails, we will need to restart reading
-		// from the passed body stream.
-		// When body is seekable, use seek to reset the streams
-		// cursor to the start.
-		// Otherwise, copy the stream into a buffer while uploading
-		// and use the buffers content on retry.
-		if sk, ok := body.(io.Seeker); ok {
-			if _, err = sk.Seek(0, io.SeekStart); err != nil {
-				return
+	for { // TODO auth.continue() strategy(true|n times|until)?
+		if r, err = http.NewRequest(method, uri, body); err != nil {
+			return
+		}
+
+		for k, vals := range c.headers {
+			for _, v := range vals {
+				r.Header.Add(k, v)
 			}
-			retryBuf = body
-		} else {
-			buff := &bytes.Buffer{}
-			retryBuf = buff
-			body = io.TeeReader(body, buff)
-		}
-		r, err = http.NewRequest(method, PathEscape(Join(c.root, path)), body)
-	} else {
-		r, err = http.NewRequest(method, PathEscape(Join(c.root, path)), nil)
-	}
-
-	if err != nil {
-		return nil, err
-	}
-
-	for k, vals := range c.headers {
-		for _, v := range vals {
-			r.Header.Add(k, v)
-		}
-	}
-
-	// make sure we read 'c.auth' only once since it will be substituted below
-	// and that is unsafe to do when multiple goroutines are running at the same time.
-	c.authMutex.Lock()
-	auth := c.auth
-	c.authMutex.Unlock()
-
-	auth.Authorize(r, method, path)
-
-	if intercept != nil {
-		intercept(r)
-	}
-
-	if c.interceptor != nil {
-		c.interceptor(method, r)
-	}
-
-	rs, err := c.c.Do(r)
-	if err != nil {
-		return nil, err
-	}
-
-	if rs.StatusCode == 401 && auth.Type() == "NoAuth" {
-		wwwAuthenticateHeader := strings.ToLower(rs.Header.Get("Www-Authenticate"))
-
-		if strings.Index(wwwAuthenticateHeader, "digest") > -1 {
-			c.authMutex.Lock()
-			c.auth = &DigestAuth{auth.User(), auth.Pass(), digestParts(rs)}
-			c.authMutex.Unlock()
-		} else if strings.Index(wwwAuthenticateHeader, "basic") > -1 {
-			c.authMutex.Lock()
-			c.auth = &BasicAuth{auth.User(), auth.Pass()}
-			c.authMutex.Unlock()
-		} else {
-			return rs, newPathError("Authorize", c.root, rs.StatusCode)
 		}

-		// retryBuf will be nil if body was nil initially so no check
-		// for body == nil is required here.
-		return c.req(method, path, retryBuf, intercept)
-	} else if rs.StatusCode == 401 {
-		return rs, newPathError("Authorize", c.root, rs.StatusCode)
+		if err = auth.Authorize(c.c, r, path); err != nil {
+			return
+		}
+
+		if intercept != nil {
+			intercept(r)
+		}
+
+		if c.interceptor != nil {
+			c.interceptor(method, r)
+		}
+
+		if rs, err = c.c.Do(r); err != nil {
+			return
+		}
+
+		if redo, err = auth.Verify(c.c, rs, path); err != nil {
+			rs.Body.Close()
+			return nil, err
+		}
+		if redo {
+			rs.Body.Close()
+			if body, err = r.GetBody(); err != nil {
+				return nil, err
+			}
+			continue
+		}
+		break
 	}

 	return rs, err
@ -131,7 +99,7 @@ func (c *Client) propfind(path string, self bool, body string, resp interface{},
 	defer rs.Body.Close()

 	if rs.StatusCode != 207 {
-		return newPathError("PROPFIND", path, rs.StatusCode)
+		return NewPathError("PROPFIND", path, rs.StatusCode)
 	}

 	return parseXML(rs.Body, resp, parse)
@ -189,7 +157,7 @@ func (c *Client) copymove(method string, oldpath string, newpath string, overwri
 		return c.copymove(method, oldpath, newpath, overwrite)
 	}

-	return newPathError(method, oldpath, s)
+	return NewPathError(method, oldpath, s)
 }

 func (c *Client) put(path string, stream io.Reader) (status int, err error) {
Author	SHA1	Message	Date
shoopea	f073d3021d	remove all debug	2024-01-20 12:33:07 +01:00
shoopea	d8c0f204df	test	2024-01-20 12:18:22 +01:00
shoopea	45e36d9254	details	2024-01-20 12:11:08 +01:00
shoopea	526c74ad21	fix	2024-01-20 12:06:08 +01:00
shoopea	1dc1a2b378	still more debug	2024-01-20 12:05:02 +01:00
shoopea	e3bd2a5fb2	even more debug	2024-01-20 11:59:18 +01:00
shoopea	331e1f8e16	more debug	2024-01-20 11:43:26 +01:00
shoopea	d59e787694	debug	2024-01-20 11:27:24 +01:00
shoopea	42ddb5a83e	migrate	2024-01-20 11:02:25 +01:00
Christoph Polcin	f9157dbec1	Update Readme	2023-06-22 14:01:37 +02:00
Yuriy Zaytsev	3cf99ede06	Fix missing last modified time on Stat()	2023-06-22 13:42:44 +02:00
Julian Imhof	ea9c8490dd	feat(auth): add support for MS-PASS typo: fix comment fix: fix verify flow and precompile cookies fix: implement requested changes fix: implement requested changes fix: implement requested changes test(auth): add test for MS-PASS fix: remove pointless return	2023-06-22 13:37:18 +02:00
Christoph Polcin	036581a6c8	io.Discard is already handeld by Body.Close()	2023-06-22 13:32:03 +02:00
Christoph Polcin	11f0c10ed2	Runs test on go 1.18, 1.19 and 1.20	2023-06-22 13:32:03 +02:00
Christoph Polcin	b601d4bcbf	Update preemtiveAuthorizer documentation	2023-06-22 13:32:03 +02:00
Christoph Polcin	9c049da1f7	Updates API	2023-06-22 13:32:03 +02:00
Christoph Polcin	fcd6cac508	Removes panic from authShim	2023-06-22 13:32:03 +02:00
Christoph Polcin	a4cd839b8a	Adds len checks to negoAuth	2023-06-22 13:32:03 +02:00
Christoph Polcin	d59c1705b2	Explicit assignment of struct fields	2023-06-22 13:32:03 +02:00
Christoph Polcin	ad27fc07a7	Adds interface documentation	2023-06-22 13:32:03 +02:00
Steffen Brüheim	5fd8037a63	Add multiple auth test	2023-06-22 13:32:03 +02:00
Christoph Polcin	ca40e2802e	Feat: Authentication API The changes simplify the `req` method by moving the authentication-related code into the API. This makes it easy to add additional authentication methods. The API introduces an `Authorizer` that acts as an authenticator factory. The authentication flow itself is divided down into `Authorize` and `Verify` steps in order to encapsulate and control complex authentication challenges. The default `NewAutoAuth` negotiates the algorithms. Under the hood, it creates an authenticator shim per request, which delegates the authentication flow to our authenticators. The `NewEmptyAuth` and `NewPreemptiveAuth` authorizers allow you to have more control over algorithms and resources. The API also allows interception of the redirect mechanism by setting the `XInhibitRedirect` header. This closes: #15 #24 #38	2023-06-22 13:32:03 +02:00
Christoph Polcin	3282f94193	Feat: Makefile adds target dependencies	2023-02-03 21:22:12 +01:00
yyeltsyn	cd21842fb6	fix: Allow concurrent use for DigestAuth (#69 ) fix: Allow concurrent use for DigestAuth	2023-02-03 18:59:54 +01:00
Steffen Brüheim	60ec5ad560	Fixes #64 Support for cookies expose a SetJar method to set a http.CookieJar to the http client	2022-11-09 18:19:24 +01:00