feat: v2 (#599)

Read https://github.com/filebrowser/filebrowser/pull/575.

Former-commit-id: 7aedcaaf72b863033e3f089d6df308d41a3fd00c [formerly bdbe4d49161b901c4adf9c245895a1be2d62e4a7] [formerly acfc1ec67c423e0b3e065a8c1f8897c5249af65b [formerly d309066def]]
Former-commit-id: 0c7d925a38a68ccabdf2c4bbd8c302ee89b93509 [formerly a6173925a1382955d93b334ded93f70d6dddd694]
Former-commit-id: e032e0804dd051df86f42962de2b39caec5318b7

auth/json.go

@@ -0,0 +1,108 @@
+package auth
+
+import (
+	"encoding/json"
+	"net/http"
+	"net/url"
+	"os"
+	"strings"
+
+	"github.com/filebrowser/filebrowser/v2/settings"
+	"github.com/filebrowser/filebrowser/v2/users"
+)
+
+// MethodJSONAuth is used to identify json auth.
+const MethodJSONAuth settings.AuthMethod = "json"
+
+type jsonCred struct {
+	Password  string `json:"password"`
+	Username  string `json:"username"`
+	ReCaptcha string `json:"recaptcha"`
+}
+
+// JSONAuth is a json implementaion of an Auther.
+type JSONAuth struct {
+	ReCaptcha *ReCaptcha
+	storage   *users.Storage
+}
+
+// Auth authenticates the user via a json in content body.
+func (a *JSONAuth) Auth(r *http.Request) (*users.User, error) {
+	var cred jsonCred
+
+	if r.Body == nil {
+		return nil, os.ErrPermission
+	}
+
+	err := json.NewDecoder(r.Body).Decode(&cred)
+	if err != nil {
+		return nil, os.ErrPermission
+	}
+
+	// If ReCaptcha is enabled, check the code.
+	if a.ReCaptcha != nil && len(a.ReCaptcha.Secret) > 0 {
+		ok, err := a.ReCaptcha.Ok(cred.ReCaptcha)
+
+		if err != nil {
+			return nil, err
+		}
+
+		if !ok {
+			return nil, os.ErrPermission
+		}
+	}
+
+	u, err := a.storage.Get(cred.Username)
+	if err != nil || !users.CheckPwd(cred.Password, u.Password) {
+		return nil, os.ErrPermission
+	}
+
+	return u, nil
+}
+
+// SetStorage attaches the storage to the auther.
+func (a *JSONAuth) SetStorage(s *users.Storage) {
+	a.storage = s
+}
+
+const reCaptchaAPI = "/recaptcha/api/siteverify"
+
+// ReCaptcha identifies a recaptcha conenction.
+type ReCaptcha struct {
+	Host   string `json:"host"`
+	Key    string `json:"key"`
+	Secret string `json:"secret"`
+}
+
+// Ok checks if a reCaptcha responde is correct.
+func (r *ReCaptcha) Ok(response string) (bool, error) {
+	body := url.Values{}
+	body.Set("secret", r.Key)
+	body.Add("response", response)
+
+	client := &http.Client{}
+
+	resp, err := client.Post(
+		r.Host+reCaptchaAPI,
+		"application/x-www-form-urlencoded",
+		strings.NewReader(body.Encode()),
+	)
+	if err != nil {
+		return false, err
+	}
+
+	if resp.StatusCode != http.StatusOK {
+		return false, nil
+	}
+
+	var data struct {
+		Success bool `json:"success"`
+	}
+
+	err = json.NewDecoder(resp.Body).Decode(&data)
+	if err != nil {
+		return false, err
+	}
+
+	return data.Success, nil
+}