OpenID authentification (#170)

* openid authentification

* openid middleware

* openId login

* tidied login page

* removed useless email text field

server/openid/handler.go

@@ -0,0 +1,172 @@
+package openid
+
+import (
+	"context"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"net/http"
+	"time"
+
+	"github.com/coreos/go-oidc"
+	"github.com/google/uuid"
+	"github.com/marcopeocchi/yt-dlp-web-ui/server/config"
+	"golang.org/x/oauth2"
+)
+
+type OAuth2SuccessResponse struct {
+	OAuth2Token    *oauth2.Token
+	OAuth2RawToken string
+	IDTokenClaims  *json.RawMessage
+}
+
+var (
+	oauth2Config oauth2.Config
+	verifier     *oidc.IDTokenVerifier
+)
+
+func Configure() {
+	provider, err := oidc.NewProvider(context.Background(), config.Instance().OpenIdProviderURL)
+	if err != nil {
+		panic(err)
+	}
+
+	oauth2Config = oauth2.Config{
+		ClientID:     config.Instance().OpenIdClientId,
+		ClientSecret: config.Instance().OpenIdClientSecret,
+		RedirectURL:  config.Instance().OpenIdRedirectURL,
+		Endpoint:     provider.Endpoint(),
+		Scopes:       []string{oidc.ScopeOpenID, "profile", "email"},
+	}
+
+	verifier = provider.Verifier(&oidc.Config{
+		ClientID: config.Instance().OpenIdClientId,
+	})
+}
+
+func Login(w http.ResponseWriter, r *http.Request) {
+	var (
+		state = uuid.NewString()
+		nonce = uuid.NewString() // maybe something cryptographycally more seucre?
+	)
+
+	http.SetCookie(w, &http.Cookie{
+		Name:     "state",
+		Value:    state,
+		HttpOnly: true,
+		Path:     "/",
+		Secure:   r.TLS != nil,
+		Expires:  time.Now().Add(time.Hour * 24 * 30),
+	})
+
+	http.SetCookie(w, &http.Cookie{
+		Name:     "nonce",
+		Value:    nonce,
+		HttpOnly: true,
+		Path:     "/",
+		Secure:   r.TLS != nil,
+		Expires:  time.Now().Add(time.Hour * 24 * 30),
+	})
+
+	http.Redirect(w, r, oauth2Config.AuthCodeURL(state, oidc.Nonce(nonce)), http.StatusFound)
+}
+
+func doAuthentification(r *http.Request) (*OAuth2SuccessResponse, error) {
+	state, err := r.Cookie("state")
+	if err != nil {
+		return nil, err
+	}
+
+	if r.URL.Query().Get("state") != state.Value {
+		return nil, errors.New("auth state does not match")
+	}
+
+	oauth2Token, err := oauth2Config.Exchange(r.Context(), r.URL.Query().Get("code"))
+	if err != nil {
+		return nil, err
+	}
+
+	rawToken, ok := oauth2Token.Extra("id_token").(string)
+	if !ok {
+		return nil, errors.New("openid field \"id_token\" not found in oauth2 token")
+	}
+
+	idToken, err := verifier.Verify(r.Context(), rawToken)
+	if err != nil {
+		return nil, err
+	}
+
+	nonce, err := r.Cookie("nonce")
+	if err != nil {
+		return nil, err
+	}
+
+	if idToken.Nonce != nonce.Value {
+		return nil, errors.New("auth nonce does not match")
+	}
+
+	// redact
+	oauth2Token.AccessToken = ""
+
+	res := OAuth2SuccessResponse{
+		oauth2Token,
+		rawToken,
+		&json.RawMessage{},
+	}
+
+	if err := idToken.Claims(&res.IDTokenClaims); err != nil {
+		return nil, err
+	}
+
+	return &res, nil
+}
+
+func SingIn(w http.ResponseWriter, r *http.Request) {
+	res, err := doAuthentification(r)
+	if err != nil {
+		http.Error(w, err.Error(), http.StatusBadRequest)
+		return
+	}
+
+	http.SetCookie(w, &http.Cookie{
+		Name:     "oid-token",
+		Value:    res.OAuth2RawToken,
+		HttpOnly: true,
+		Path:     "/",
+		Secure:   r.TLS != nil,
+		Expires:  time.Now().Add(time.Hour * 24 * 30),
+	})
+
+	// if err := json.NewEncoder(w).Encode(res); err != nil {
+	// 	http.Error(w, err.Error(), http.StatusInternalServerError)
+	// 	return
+	// }
+
+	fmt.Fprintf(w, "Login succesfully, you may now close this window and refresh yt-dlp-webui.")
+}
+
+func Logout(w http.ResponseWriter, r *http.Request) {
+	http.SetCookie(w, &http.Cookie{
+		Name:     "oid-token",
+		HttpOnly: true,
+		Path:     "/",
+		Secure:   r.TLS != nil,
+		Expires:  time.Now(),
+	})
+
+	http.SetCookie(w, &http.Cookie{
+		Name:     "state",
+		HttpOnly: true,
+		Path:     "/",
+		Secure:   r.TLS != nil,
+		Expires:  time.Now(),
+	})
+
+	http.SetCookie(w, &http.Cookie{
+		Name:     "nonce",
+		HttpOnly: true,
+		Path:     "/",
+		Secure:   r.TLS != nil,
+		Expires:  time.Now(),
+	})
+}

server/openid/middleware.go

@@ -0,0 +1,20 @@
+package openid
+
+import "net/http"
+
+func Middleware(next http.Handler) http.Handler {
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		token, err := r.Cookie("oid-token")
+		if err != nil {
+			http.Error(w, err.Error(), http.StatusBadRequest)
+			return
+		}
+
+		if _, err := verifier.Verify(r.Context(), token.Value); err != nil {
+			http.Error(w, err.Error(), http.StatusBadRequest)
+			return
+		}
+
+		next.ServeHTTP(w, r)
+	})
+}