GoDoxy/internal/api/v1/auth/oidc.go
2025-04-23 02:02:17 +08:00

272 lines
7.1 KiB
Go

package auth
import (
"context"
"errors"
"fmt"
"net/http"
"net/url"
"slices"
"time"
"github.com/coreos/go-oidc/v3/oidc"
"github.com/yusing/go-proxy/internal/common"
"github.com/yusing/go-proxy/internal/logging"
"github.com/yusing/go-proxy/internal/net/gphttp"
"github.com/yusing/go-proxy/internal/utils"
"github.com/yusing/go-proxy/internal/utils/strutils"
"golang.org/x/oauth2"
)
type (
OIDCProvider struct {
oauthConfig *oauth2.Config
oidcProvider *oidc.Provider
oidcVerifier *oidc.IDTokenVerifier
oidcEndSessionURL *url.URL
allowedUsers []string
allowedGroups []string
}
providerJSON struct {
oidc.ProviderConfig
EndSessionURL string `json:"end_session_endpoint"`
}
)
const CookieOauthState = "godoxy_oidc_state"
const (
OIDCAuthCallbackPath = "/auth/callback"
OIDCPostAuthPath = "/auth/postauth"
OIDCLogoutPath = "/auth/logout"
)
var (
ErrMissingState = errors.New("missing state cookie")
ErrInvalidState = errors.New("invalid oauth state")
)
func NewOIDCProvider(issuerURL, clientID, clientSecret string, allowedUsers, allowedGroups []string) (*OIDCProvider, error) {
if len(allowedUsers)+len(allowedGroups) == 0 {
return nil, errors.New("OIDC users, groups, or both must not be empty")
}
provider, err := oidc.NewProvider(context.Background(), issuerURL)
if err != nil {
return nil, fmt.Errorf("failed to initialize OIDC provider: %w", err)
}
endSessionURL, err := url.Parse(provider.EndSessionEndpoint())
if err != nil && provider.EndSessionEndpoint() != "" {
// non critical, just warn
logging.Warn().
Str("issuer", issuerURL).
Err(err).
Msg("failed to parse end session URL")
}
return &OIDCProvider{
oauthConfig: &oauth2.Config{
ClientID: clientID,
ClientSecret: clientSecret,
RedirectURL: "",
Endpoint: provider.Endpoint(),
Scopes: strutils.CommaSeperatedList(common.OIDCScopes),
},
oidcProvider: provider,
oidcVerifier: provider.Verifier(&oidc.Config{
ClientID: clientID,
}),
oidcEndSessionURL: endSessionURL,
allowedUsers: allowedUsers,
allowedGroups: allowedGroups,
}, nil
}
// NewOIDCProviderFromEnv creates a new OIDCProvider from environment variables.
func NewOIDCProviderFromEnv() (*OIDCProvider, error) {
return NewOIDCProvider(
common.OIDCIssuerURL,
common.OIDCClientID,
common.OIDCClientSecret,
common.OIDCAllowedUsers,
common.OIDCAllowedGroups,
)
}
func (auth *OIDCProvider) TokenCookieName() string {
return "godoxy_oidc_token"
}
func (auth *OIDCProvider) SetAllowedUsers(users []string) {
auth.allowedUsers = users
}
func (auth *OIDCProvider) SetAllowedGroups(groups []string) {
auth.allowedGroups = groups
}
func (auth *OIDCProvider) getVerifyStateCookie(r *http.Request) (string, error) {
state, err := r.Cookie(CookieOauthState)
if err != nil {
return "", ErrMissingState
}
if r.URL.Query().Get("state") != state.Value {
return "", ErrInvalidState
}
return state.Value, nil
}
func optRedirectPostAuth(r *http.Request) oauth2.AuthCodeOption {
return oauth2.SetAuthURLParam("redirect_uri", "https://"+r.Host+OIDCPostAuthPath)
}
func (auth *OIDCProvider) HandleAuth(w http.ResponseWriter, r *http.Request) {
switch r.Method {
case http.MethodHead:
w.WriteHeader(http.StatusOK)
return
case http.MethodGet:
break
default:
gphttp.Forbidden(w, "method not allowed")
return
}
switch r.URL.Path {
case OIDCAuthCallbackPath:
state := generateState()
http.SetCookie(w, &http.Cookie{
Name: CookieOauthState,
Value: state,
MaxAge: 300,
HttpOnly: true,
SameSite: http.SameSiteLaxMode,
Secure: common.APIJWTSecure,
Path: "/",
})
// redirect user to Idp
http.Redirect(w, r, auth.oauthConfig.AuthCodeURL(state, optRedirectPostAuth(r)), http.StatusTemporaryRedirect)
case OIDCPostAuthPath:
auth.PostAuthCallbackHandler(w, r)
default:
auth.LogoutHandler(w, r)
}
}
func (auth *OIDCProvider) CheckToken(r *http.Request) error {
token, err := r.Cookie(auth.TokenCookieName())
if err != nil {
return ErrMissingToken
}
// checks for Expiry, Audience == ClientID, Issuer, etc.
idToken, err := auth.oidcVerifier.Verify(r.Context(), token.Value)
if err != nil {
return fmt.Errorf("failed to verify ID token: %w: %w", ErrInvalidToken, err)
}
if len(idToken.Audience) == 0 {
return ErrInvalidToken
}
var claims struct {
Email string `json:"email"`
Username string `json:"preferred_username"`
Groups []string `json:"groups"`
}
if err := idToken.Claims(&claims); err != nil {
return fmt.Errorf("failed to parse claims: %w", err)
}
// Logical AND between allowed users and groups.
allowedUser := slices.Contains(auth.allowedUsers, claims.Username)
allowedGroup := len(utils.Intersect(claims.Groups, auth.allowedGroups)) > 0
if !allowedUser && !allowedGroup {
return ErrUserNotAllowed
}
return nil
}
func (auth *OIDCProvider) RedirectLoginPage(w http.ResponseWriter, r *http.Request) {
http.Redirect(w, r, "/", http.StatusTemporaryRedirect)
}
func (auth *OIDCProvider) PostAuthCallbackHandler(w http.ResponseWriter, r *http.Request) {
// For testing purposes, skip provider verification
if common.IsTest {
auth.handleTestCallback(w, r)
return
}
_, err := auth.getVerifyStateCookie(r)
if err != nil {
gphttp.BadRequest(w, err.Error())
return
}
code := r.URL.Query().Get("code")
oauth2Token, err := auth.oauthConfig.Exchange(r.Context(), code, optRedirectPostAuth(r))
if err != nil {
gphttp.ServerError(w, r, fmt.Errorf("failed to exchange token: %w", err))
return
}
rawIDToken, ok := oauth2Token.Extra("id_token").(string)
if !ok {
gphttp.BadRequest(w, "missing id_token")
return
}
idToken, err := auth.oidcVerifier.Verify(r.Context(), rawIDToken)
if err != nil {
gphttp.ServerError(w, r, fmt.Errorf("failed to verify ID token: %w", err))
return
}
setTokenCookie(w, r, auth.TokenCookieName(), rawIDToken, time.Until(idToken.Expiry))
// Redirect to home page
http.Redirect(w, r, "/", http.StatusTemporaryRedirect)
}
func (auth *OIDCProvider) LogoutHandler(w http.ResponseWriter, r *http.Request) {
if auth.oidcEndSessionURL == nil {
clearTokenCookie(w, r, auth.TokenCookieName())
http.Redirect(w, r, OIDCAuthCallbackPath, http.StatusTemporaryRedirect)
return
}
token, err := r.Cookie(auth.TokenCookieName())
if err == nil {
query := auth.oidcEndSessionURL.Query()
query.Add("id_token_hint", token.Value)
logoutURL := *auth.oidcEndSessionURL
logoutURL.RawQuery = query.Encode()
clearTokenCookie(w, r, auth.TokenCookieName())
http.Redirect(w, r, logoutURL.String(), http.StatusFound)
}
http.Redirect(w, r, OIDCAuthCallbackPath, http.StatusTemporaryRedirect)
}
// handleTestCallback handles OIDC callback in test environment.
func (auth *OIDCProvider) handleTestCallback(w http.ResponseWriter, r *http.Request) {
state, err := r.Cookie(CookieOauthState)
if err != nil {
gphttp.BadRequest(w, "missing state cookie")
return
}
if r.URL.Query().Get("state") != state.Value {
gphttp.BadRequest(w, "invalid oauth state")
return
}
// Create test JWT token
setTokenCookie(w, r, auth.TokenCookieName(), "test", time.Hour)
http.Redirect(w, r, "/", http.StatusTemporaryRedirect)
}