nextcloud oauth (#10562)

Fix #7078

vendor/github.com/markbates/goth/providers/nextcloud/README.md

@@ -0,0 +1,85 @@
+# Nextcloud OAuth2
+
+For this backend, you need to have an OAuth2 enabled Nextcloud Instance, e.g.
+on your own private server.
+
+## Setting up Nextcloud Test Environment
+
+To test, you only need a working Docker image of Nextcloud running on a public
+URL, e.g. through [traefik](https://traefik.io/)
+
+```docker-compose.yml
+version: '2'
+
+networks:
+  traefik-web:
+    external: true
+
+services:
+  app:
+    image: nextcloud
+    restart: always
+    networks:
+      - traefik-web
+    labels:
+      - traefik.enable=true
+      - traefik.frontend.rule=Host:${NEXTCLOUD_DNS}
+      - traefik.docker.network=traefik-web
+    environment:
+      SQLITE_DATABASE: "database.sqlite3"
+      NEXTCLOUD_ADMIN_USER: admin
+      NEXTCLOUD_ADMIN_PASSWORD: admin
+      NEXTCLOUD_TRUSTED_DOMAINS: ${NEXTCLOUD_DNS}
+```
+
+and start it up via
+
+```
+NEXTCLOUD_DNS=goth.my.server.name docker-compose up -d
+```
+
+afterwards, you will have a running Nextcloud instance with credentials
+
+```
+admin / admin
+```
+
+Then add a new OAuth 2.0 Client by going to
+
+```
+Settings -> Security -> OAuth 2.0 client
+```
+
+![Nextcloud Setup](nextcloud_setup.png)
+
+and add a new client with the name `goth` and redirection uri `http://localhost:3000/auth/nextcloud/callback`. The imporant part here the
+two cryptic entries `Client Identifier` and `Secret`, which needs to be
+used in your application.
+
+## Running Login Example
+
+If you want to run the default example in `<goth>/examples`, you have to 
+retrieve the keys described in the previous section and run the example
+as follows:
+
+```
+NEXTCLOUD_URL=https://goth.my.server.name \
+NEXTCLOUD_KEY=<your-key> \
+NEXTCLOUD_SECRET=<your-secret> \
+SESSION_SECRET=1 \
+./examples
+```
+
+Afterwards, you should be able to login via Nextcloud in the examples app.
+
+## Running the Provider Test
+
+The test has the same arguments as the login example test, but starts the test itself
+
+```
+NEXTCLOUD_URL=https://goth.my.server.name \
+NEXTCLOUD_KEY=<your-key> \
+NEXTCLOUD_SECRET=<your-secret> \
+SESSION_SECRET=1 \
+go test -v
+```

vendor/github.com/markbates/goth/providers/nextcloud/nextcloud.go

@@ -0,0 +1,208 @@
+// Package nextcloud implements the OAuth2 protocol for authenticating users through nextcloud.
+// This package can be used as a reference implementation of an OAuth2 provider for Goth.
+package nextcloud
+
+import (
+	"bytes"
+	"encoding/json"
+	"io"
+	"io/ioutil"
+	"net/http"
+
+	"fmt"
+
+	"github.com/markbates/goth"
+	"golang.org/x/oauth2"
+)
+
+// These vars define the Authentication, Token, and Profile URLS for Nextcloud.
+// You have to set these values to something useful, because nextcloud is always
+// hosted somewhere.
+//
+var (
+	AuthURL    = "https://<own-server>/apps/oauth2/authorize"
+	TokenURL   = "https://<own-server>/apps/oauth2/api/v1/token"
+	ProfileURL = "https://<own-server>/ocs/v2.php/cloud/user?format=json"
+)
+
+// Provider is the implementation of `goth.Provider` for accessing Nextcloud.
+type Provider struct {
+	ClientKey    string
+	Secret       string
+	CallbackURL  string
+	HTTPClient   *http.Client
+	config       *oauth2.Config
+	providerName string
+	authURL      string
+	tokenURL     string
+	profileURL   string
+}
+
+// New is only here to fulfill the interface requirements and does not work properly without
+// setting your own Nextcloud connect parameters, more precisely AuthURL, TokenURL and ProfileURL.
+// Please use NewCustomisedDNS with the beginning of your URL or NewCustomiseURL.
+func New(clientKey, secret, callbackURL string, scopes ...string) *Provider {
+	return NewCustomisedURL(clientKey, secret, callbackURL, AuthURL, TokenURL, ProfileURL, scopes...)
+}
+
+// NewCustomisedURL create a working connection to your Nextcloud server given by the values
+// authURL, tokenURL and profileURL.
+// If you want to use a simpler method, please have a look at NewCustomisedDNS, which gets only
+// on parameter instead of three.
+func NewCustomisedURL(clientKey, secret, callbackURL, authURL, tokenURL, profileURL string, scopes ...string) *Provider {
+	p := &Provider{
+		ClientKey:    clientKey,
+		Secret:       secret,
+		CallbackURL:  callbackURL,
+		providerName: "nextcloud",
+		profileURL:   profileURL,
+	}
+	p.config = newConfig(p, authURL, tokenURL, scopes)
+	return p
+}
+
+// NewCustomisedDNS is the simplest method to create a provider based only on your key/secret
+// and the beginning of the URL to your server, e.g. https://my.server.name/
+func NewCustomisedDNS(clientKey, secret, callbackURL, nextcloudURL string, scopes ...string) *Provider {
+	return NewCustomisedURL(
+		clientKey,
+		secret,
+		callbackURL,
+		nextcloudURL+"/apps/oauth2/authorize",
+		nextcloudURL+"/apps/oauth2/api/v1/token",
+		nextcloudURL+"/ocs/v2.php/cloud/user?format=json",
+		scopes...,
+	)
+}
+
+// Name is the name used to retrieve this provider later.
+func (p *Provider) Name() string {
+	return p.providerName
+}
+
+// SetName is to update the name of the provider (needed in case of multiple providers of 1 type)
+func (p *Provider) SetName(name string) {
+	p.providerName = name
+}
+
+func (p *Provider) Client() *http.Client {
+	return goth.HTTPClientWithFallBack(p.HTTPClient)
+}
+
+// Debug is a no-op for the nextcloud package.
+func (p *Provider) Debug(debug bool) {}
+
+// BeginAuth asks Nextcloud for an authentication end-point.
+func (p *Provider) BeginAuth(state string) (goth.Session, error) {
+	return &Session{
+		AuthURL: p.config.AuthCodeURL(state),
+	}, nil
+}
+
+// FetchUser will go to Nextcloud and access basic information about the user.
+func (p *Provider) FetchUser(session goth.Session) (goth.User, error) {
+	sess := session.(*Session)
+	user := goth.User{
+		AccessToken:  sess.AccessToken,
+		Provider:     p.Name(),
+		RefreshToken: sess.RefreshToken,
+		ExpiresAt:    sess.ExpiresAt,
+	}
+
+	if user.AccessToken == "" {
+		// data is not yet retrieved since accessToken is still empty
+		return user, fmt.Errorf("%s cannot get user information without accessToken", p.providerName)
+	}
+
+	req, err := http.NewRequest("GET", p.profileURL, nil)
+	if err != nil {
+		return user, err
+	}
+	req.Header.Set("Authorization", "Bearer "+sess.AccessToken)
+	response, err := p.Client().Do(req)
+
+	if err != nil {
+		if response != nil {
+			response.Body.Close()
+		}
+		return user, err
+	}
+
+	defer response.Body.Close()
+
+	if response.StatusCode != http.StatusOK {
+		return user, fmt.Errorf("%s responded with a %d trying to fetch user information", p.providerName, response.StatusCode)
+	}
+
+	bits, err := ioutil.ReadAll(response.Body)
+	if err != nil {
+		return user, err
+	}
+
+	err = json.NewDecoder(bytes.NewReader(bits)).Decode(&user.RawData)
+	if err != nil {
+		return user, err
+	}
+
+	err = userFromReader(bytes.NewReader(bits), &user)
+
+	return user, err
+}
+
+func newConfig(provider *Provider, authURL, tokenURL string, scopes []string) *oauth2.Config {
+	c := &oauth2.Config{
+		ClientID:     provider.ClientKey,
+		ClientSecret: provider.Secret,
+		RedirectURL:  provider.CallbackURL,
+		Endpoint: oauth2.Endpoint{
+			AuthURL:  authURL,
+			TokenURL: tokenURL,
+		},
+		Scopes: []string{},
+	}
+
+	if len(scopes) > 0 {
+		for _, scope := range scopes {
+			c.Scopes = append(c.Scopes, scope)
+		}
+	}
+	return c
+}
+
+func userFromReader(r io.Reader, user *goth.User) error {
+	u := struct {
+		Ocs struct {
+			Data struct {
+				EMail       string `json:"email"`
+				DisplayName string `json:"display-name"`
+				ID          string `json:"id"`
+				Address     string `json:"address"`
+			}
+		} `json:"ocs"`
+	}{}
+	err := json.NewDecoder(r).Decode(&u)
+	if err != nil {
+		return err
+	}
+	user.Email = u.Ocs.Data.EMail
+	user.Name = u.Ocs.Data.DisplayName
+	user.UserID = u.Ocs.Data.ID
+	user.Location = u.Ocs.Data.Address
+	return nil
+}
+
+//RefreshTokenAvailable refresh token is provided by auth provider or not
+func (p *Provider) RefreshTokenAvailable() bool {
+	return true
+}
+
+//RefreshToken get new access token based on the refresh token
+func (p *Provider) RefreshToken(refreshToken string) (*oauth2.Token, error) {
+	token := &oauth2.Token{RefreshToken: refreshToken}
+	ts := p.config.TokenSource(goth.ContextForClient(p.Client()), token)
+	newToken, err := ts.Token()
+	if err != nil {
+		return nil, err
+	}
+	return newToken, err
+}

vendor/github.com/markbates/goth/providers/nextcloud/session.go

@@ -0,0 +1,63 @@
+package nextcloud
+
+import (
+	"encoding/json"
+	"errors"
+	"strings"
+	"time"
+
+	"github.com/markbates/goth"
+)
+
+// Session stores data during the auth process with Nextcloud.
+type Session struct {
+	AuthURL      string
+	AccessToken  string
+	RefreshToken string
+	ExpiresAt    time.Time
+}
+
+var _ goth.Session = &Session{}
+
+// GetAuthURL will return the URL set by calling the `BeginAuth` function on the Nextcloud provider.
+func (s Session) GetAuthURL() (string, error) {
+	if s.AuthURL == "" {
+		return "", errors.New(goth.NoAuthUrlErrorMessage)
+	}
+	return s.AuthURL, nil
+}
+
+// Authorize the session with Nextcloud and return the access token to be stored for future use.
+func (s *Session) Authorize(provider goth.Provider, params goth.Params) (string, error) {
+	p := provider.(*Provider)
+	token, err := p.config.Exchange(goth.ContextForClient(p.Client()), params.Get("code"))
+	if err != nil {
+		return "", err
+	}
+
+	if !token.Valid() {
+		return "", errors.New("Invalid token received from provider")
+	}
+
+	s.AccessToken = token.AccessToken
+	s.RefreshToken = token.RefreshToken
+	s.ExpiresAt = token.Expiry
+	return token.AccessToken, err
+}
+
+// Marshal the session into a string
+func (s Session) Marshal() string {
+	b, _ := json.Marshal(s)
+	return string(b)
+}
+
+func (s Session) String() string {
+	return s.Marshal()
+}
+
+// UnmarshalSession wil unmarshal a JSON string into a session.
+func (p *Provider) UnmarshalSession(data string) (goth.Session, error) {
+	s := &Session{}
+	err := json.NewDecoder(strings.NewReader(data)).Decode(s)
+	return s, err
+}