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forgejo/routers/web/user/oauth.go
KN4CK3R 88abb0dc8a
Decoupled code from DefaultSigningKey (#16743)
Decoupled code from `DefaultSigningKey`. Makes testing a little bit easier and is cleaner.
2021-08-27 20:28:00 +01:00

704 lines
22 KiB
Go

// Copyright 2019 The Gitea Authors. All rights reserved.
// Use of this source code is governed by a MIT-style
// license that can be found in the LICENSE file.
package user
import (
"encoding/base64"
"fmt"
"html"
"net/http"
"net/url"
"strings"
"code.gitea.io/gitea/models"
"code.gitea.io/gitea/modules/base"
"code.gitea.io/gitea/modules/context"
"code.gitea.io/gitea/modules/json"
"code.gitea.io/gitea/modules/log"
"code.gitea.io/gitea/modules/setting"
"code.gitea.io/gitea/modules/timeutil"
"code.gitea.io/gitea/modules/web"
"code.gitea.io/gitea/services/auth"
"code.gitea.io/gitea/services/auth/source/oauth2"
"code.gitea.io/gitea/services/forms"
"gitea.com/go-chi/binding"
"github.com/golang-jwt/jwt"
)
const (
tplGrantAccess base.TplName = "user/auth/grant"
tplGrantError base.TplName = "user/auth/grant_error"
)
// TODO move error and responses to SDK or models
// AuthorizeErrorCode represents an error code specified in RFC 6749
type AuthorizeErrorCode string
const (
// ErrorCodeInvalidRequest represents the according error in RFC 6749
ErrorCodeInvalidRequest AuthorizeErrorCode = "invalid_request"
// ErrorCodeUnauthorizedClient represents the according error in RFC 6749
ErrorCodeUnauthorizedClient AuthorizeErrorCode = "unauthorized_client"
// ErrorCodeAccessDenied represents the according error in RFC 6749
ErrorCodeAccessDenied AuthorizeErrorCode = "access_denied"
// ErrorCodeUnsupportedResponseType represents the according error in RFC 6749
ErrorCodeUnsupportedResponseType AuthorizeErrorCode = "unsupported_response_type"
// ErrorCodeInvalidScope represents the according error in RFC 6749
ErrorCodeInvalidScope AuthorizeErrorCode = "invalid_scope"
// ErrorCodeServerError represents the according error in RFC 6749
ErrorCodeServerError AuthorizeErrorCode = "server_error"
// ErrorCodeTemporaryUnavailable represents the according error in RFC 6749
ErrorCodeTemporaryUnavailable AuthorizeErrorCode = "temporarily_unavailable"
)
// AuthorizeError represents an error type specified in RFC 6749
type AuthorizeError struct {
ErrorCode AuthorizeErrorCode `json:"error" form:"error"`
ErrorDescription string
State string
}
// Error returns the error message
func (err AuthorizeError) Error() string {
return fmt.Sprintf("%s: %s", err.ErrorCode, err.ErrorDescription)
}
// AccessTokenErrorCode represents an error code specified in RFC 6749
type AccessTokenErrorCode string
const (
// AccessTokenErrorCodeInvalidRequest represents an error code specified in RFC 6749
AccessTokenErrorCodeInvalidRequest AccessTokenErrorCode = "invalid_request"
// AccessTokenErrorCodeInvalidClient represents an error code specified in RFC 6749
AccessTokenErrorCodeInvalidClient = "invalid_client"
// AccessTokenErrorCodeInvalidGrant represents an error code specified in RFC 6749
AccessTokenErrorCodeInvalidGrant = "invalid_grant"
// AccessTokenErrorCodeUnauthorizedClient represents an error code specified in RFC 6749
AccessTokenErrorCodeUnauthorizedClient = "unauthorized_client"
// AccessTokenErrorCodeUnsupportedGrantType represents an error code specified in RFC 6749
AccessTokenErrorCodeUnsupportedGrantType = "unsupported_grant_type"
// AccessTokenErrorCodeInvalidScope represents an error code specified in RFC 6749
AccessTokenErrorCodeInvalidScope = "invalid_scope"
)
// AccessTokenError represents an error response specified in RFC 6749
type AccessTokenError struct {
ErrorCode AccessTokenErrorCode `json:"error" form:"error"`
ErrorDescription string `json:"error_description"`
}
// Error returns the error message
func (err AccessTokenError) Error() string {
return fmt.Sprintf("%s: %s", err.ErrorCode, err.ErrorDescription)
}
// TokenType specifies the kind of token
type TokenType string
const (
// TokenTypeBearer represents a token type specified in RFC 6749
TokenTypeBearer TokenType = "bearer"
// TokenTypeMAC represents a token type specified in RFC 6749
TokenTypeMAC = "mac"
)
// AccessTokenResponse represents a successful access token response
type AccessTokenResponse struct {
AccessToken string `json:"access_token"`
TokenType TokenType `json:"token_type"`
ExpiresIn int64 `json:"expires_in"`
RefreshToken string `json:"refresh_token"`
IDToken string `json:"id_token,omitempty"`
}
func newAccessTokenResponse(grant *models.OAuth2Grant, serverKey, clientKey oauth2.JWTSigningKey) (*AccessTokenResponse, *AccessTokenError) {
if setting.OAuth2.InvalidateRefreshTokens {
if err := grant.IncreaseCounter(); err != nil {
return nil, &AccessTokenError{
ErrorCode: AccessTokenErrorCodeInvalidGrant,
ErrorDescription: "cannot increase the grant counter",
}
}
}
// generate access token to access the API
expirationDate := timeutil.TimeStampNow().Add(setting.OAuth2.AccessTokenExpirationTime)
accessToken := &oauth2.Token{
GrantID: grant.ID,
Type: oauth2.TypeAccessToken,
StandardClaims: jwt.StandardClaims{
ExpiresAt: expirationDate.AsTime().Unix(),
},
}
signedAccessToken, err := accessToken.SignToken(serverKey)
if err != nil {
return nil, &AccessTokenError{
ErrorCode: AccessTokenErrorCodeInvalidRequest,
ErrorDescription: "cannot sign token",
}
}
// generate refresh token to request an access token after it expired later
refreshExpirationDate := timeutil.TimeStampNow().Add(setting.OAuth2.RefreshTokenExpirationTime * 60 * 60).AsTime().Unix()
refreshToken := &oauth2.Token{
GrantID: grant.ID,
Counter: grant.Counter,
Type: oauth2.TypeRefreshToken,
StandardClaims: jwt.StandardClaims{
ExpiresAt: refreshExpirationDate,
},
}
signedRefreshToken, err := refreshToken.SignToken(serverKey)
if err != nil {
return nil, &AccessTokenError{
ErrorCode: AccessTokenErrorCodeInvalidRequest,
ErrorDescription: "cannot sign token",
}
}
// generate OpenID Connect id_token
signedIDToken := ""
if grant.ScopeContains("openid") {
app, err := models.GetOAuth2ApplicationByID(grant.ApplicationID)
if err != nil {
return nil, &AccessTokenError{
ErrorCode: AccessTokenErrorCodeInvalidRequest,
ErrorDescription: "cannot find application",
}
}
user, err := models.GetUserByID(grant.UserID)
if err != nil {
if models.IsErrUserNotExist(err) {
return nil, &AccessTokenError{
ErrorCode: AccessTokenErrorCodeInvalidRequest,
ErrorDescription: "cannot find user",
}
}
log.Error("Error loading user: %v", err)
return nil, &AccessTokenError{
ErrorCode: AccessTokenErrorCodeInvalidRequest,
ErrorDescription: "server error",
}
}
idToken := &oauth2.OIDCToken{
StandardClaims: jwt.StandardClaims{
ExpiresAt: expirationDate.AsTime().Unix(),
Issuer: setting.AppURL,
Audience: app.ClientID,
Subject: fmt.Sprint(grant.UserID),
},
Nonce: grant.Nonce,
}
if grant.ScopeContains("profile") {
idToken.Name = user.FullName
idToken.PreferredUsername = user.Name
idToken.Profile = user.HTMLURL()
idToken.Picture = user.AvatarLink()
idToken.Website = user.Website
idToken.Locale = user.Language
idToken.UpdatedAt = user.UpdatedUnix
}
if grant.ScopeContains("email") {
idToken.Email = user.Email
idToken.EmailVerified = user.IsActive
}
signedIDToken, err = idToken.SignToken(clientKey)
if err != nil {
return nil, &AccessTokenError{
ErrorCode: AccessTokenErrorCodeInvalidRequest,
ErrorDescription: "cannot sign token",
}
}
}
return &AccessTokenResponse{
AccessToken: signedAccessToken,
TokenType: TokenTypeBearer,
ExpiresIn: setting.OAuth2.AccessTokenExpirationTime,
RefreshToken: signedRefreshToken,
IDToken: signedIDToken,
}, nil
}
type userInfoResponse struct {
Sub string `json:"sub"`
Name string `json:"name"`
Username string `json:"preferred_username"`
Email string `json:"email"`
Picture string `json:"picture"`
}
// InfoOAuth manages request for userinfo endpoint
func InfoOAuth(ctx *context.Context) {
if ctx.User == nil || ctx.Data["AuthedMethod"] != (&auth.OAuth2{}).Name() {
ctx.Resp.Header().Set("WWW-Authenticate", `Bearer realm=""`)
ctx.HandleText(http.StatusUnauthorized, "no valid authorization")
return
}
response := &userInfoResponse{
Sub: fmt.Sprint(ctx.User.ID),
Name: ctx.User.FullName,
Username: ctx.User.Name,
Email: ctx.User.Email,
Picture: ctx.User.AvatarLink(),
}
ctx.JSON(http.StatusOK, response)
}
// IntrospectOAuth introspects an oauth token
func IntrospectOAuth(ctx *context.Context) {
if ctx.User == nil {
ctx.Resp.Header().Set("WWW-Authenticate", `Bearer realm=""`)
ctx.HandleText(http.StatusUnauthorized, "no valid authorization")
return
}
var response struct {
Active bool `json:"active"`
Scope string `json:"scope,omitempty"`
jwt.StandardClaims
}
form := web.GetForm(ctx).(*forms.IntrospectTokenForm)
token, err := oauth2.ParseToken(form.Token, oauth2.DefaultSigningKey)
if err == nil {
if token.Valid() == nil {
grant, err := models.GetOAuth2GrantByID(token.GrantID)
if err == nil && grant != nil {
app, err := models.GetOAuth2ApplicationByID(grant.ApplicationID)
if err == nil && app != nil {
response.Active = true
response.Scope = grant.Scope
response.Issuer = setting.AppURL
response.Audience = app.ClientID
response.Subject = fmt.Sprint(grant.UserID)
}
}
}
}
ctx.JSON(http.StatusOK, response)
}
// AuthorizeOAuth manages authorize requests
func AuthorizeOAuth(ctx *context.Context) {
form := web.GetForm(ctx).(*forms.AuthorizationForm)
errs := binding.Errors{}
errs = form.Validate(ctx.Req, errs)
if len(errs) > 0 {
errstring := ""
for _, e := range errs {
errstring += e.Error() + "\n"
}
ctx.ServerError("AuthorizeOAuth: Validate: ", fmt.Errorf("errors occurred during validation: %s", errstring))
return
}
app, err := models.GetOAuth2ApplicationByClientID(form.ClientID)
if err != nil {
if models.IsErrOauthClientIDInvalid(err) {
handleAuthorizeError(ctx, AuthorizeError{
ErrorCode: ErrorCodeUnauthorizedClient,
ErrorDescription: "Client ID not registered",
State: form.State,
}, "")
return
}
ctx.ServerError("GetOAuth2ApplicationByClientID", err)
return
}
if err := app.LoadUser(); err != nil {
ctx.ServerError("LoadUser", err)
return
}
if !app.ContainsRedirectURI(form.RedirectURI) {
handleAuthorizeError(ctx, AuthorizeError{
ErrorCode: ErrorCodeInvalidRequest,
ErrorDescription: "Unregistered Redirect URI",
State: form.State,
}, "")
return
}
if form.ResponseType != "code" {
handleAuthorizeError(ctx, AuthorizeError{
ErrorCode: ErrorCodeUnsupportedResponseType,
ErrorDescription: "Only code response type is supported.",
State: form.State,
}, form.RedirectURI)
return
}
// pkce support
switch form.CodeChallengeMethod {
case "S256":
case "plain":
if err := ctx.Session.Set("CodeChallengeMethod", form.CodeChallengeMethod); err != nil {
handleAuthorizeError(ctx, AuthorizeError{
ErrorCode: ErrorCodeServerError,
ErrorDescription: "cannot set code challenge method",
State: form.State,
}, form.RedirectURI)
return
}
if err := ctx.Session.Set("CodeChallengeMethod", form.CodeChallenge); err != nil {
handleAuthorizeError(ctx, AuthorizeError{
ErrorCode: ErrorCodeServerError,
ErrorDescription: "cannot set code challenge",
State: form.State,
}, form.RedirectURI)
return
}
// Here we're just going to try to release the session early
if err := ctx.Session.Release(); err != nil {
// we'll tolerate errors here as they *should* get saved elsewhere
log.Error("Unable to save changes to the session: %v", err)
}
case "":
break
default:
handleAuthorizeError(ctx, AuthorizeError{
ErrorCode: ErrorCodeInvalidRequest,
ErrorDescription: "unsupported code challenge method",
State: form.State,
}, form.RedirectURI)
return
}
grant, err := app.GetGrantByUserID(ctx.User.ID)
if err != nil {
handleServerError(ctx, form.State, form.RedirectURI)
return
}
// Redirect if user already granted access
if grant != nil {
code, err := grant.GenerateNewAuthorizationCode(form.RedirectURI, form.CodeChallenge, form.CodeChallengeMethod)
if err != nil {
handleServerError(ctx, form.State, form.RedirectURI)
return
}
redirect, err := code.GenerateRedirectURI(form.State)
if err != nil {
handleServerError(ctx, form.State, form.RedirectURI)
return
}
// Update nonce to reflect the new session
if len(form.Nonce) > 0 {
err := grant.SetNonce(form.Nonce)
if err != nil {
log.Error("Unable to update nonce: %v", err)
}
}
ctx.Redirect(redirect.String(), 302)
return
}
// show authorize page to grant access
ctx.Data["Application"] = app
ctx.Data["RedirectURI"] = form.RedirectURI
ctx.Data["State"] = form.State
ctx.Data["Scope"] = form.Scope
ctx.Data["Nonce"] = form.Nonce
ctx.Data["ApplicationUserLink"] = "<a href=\"" + html.EscapeString(setting.AppURL) + html.EscapeString(url.PathEscape(app.User.LowerName)) + "\">@" + html.EscapeString(app.User.Name) + "</a>"
ctx.Data["ApplicationRedirectDomainHTML"] = "<strong>" + html.EscapeString(form.RedirectURI) + "</strong>"
// TODO document SESSION <=> FORM
err = ctx.Session.Set("client_id", app.ClientID)
if err != nil {
handleServerError(ctx, form.State, form.RedirectURI)
log.Error(err.Error())
return
}
err = ctx.Session.Set("redirect_uri", form.RedirectURI)
if err != nil {
handleServerError(ctx, form.State, form.RedirectURI)
log.Error(err.Error())
return
}
err = ctx.Session.Set("state", form.State)
if err != nil {
handleServerError(ctx, form.State, form.RedirectURI)
log.Error(err.Error())
return
}
// Here we're just going to try to release the session early
if err := ctx.Session.Release(); err != nil {
// we'll tolerate errors here as they *should* get saved elsewhere
log.Error("Unable to save changes to the session: %v", err)
}
ctx.HTML(http.StatusOK, tplGrantAccess)
}
// GrantApplicationOAuth manages the post request submitted when a user grants access to an application
func GrantApplicationOAuth(ctx *context.Context) {
form := web.GetForm(ctx).(*forms.GrantApplicationForm)
if ctx.Session.Get("client_id") != form.ClientID || ctx.Session.Get("state") != form.State ||
ctx.Session.Get("redirect_uri") != form.RedirectURI {
ctx.Error(http.StatusBadRequest)
return
}
app, err := models.GetOAuth2ApplicationByClientID(form.ClientID)
if err != nil {
ctx.ServerError("GetOAuth2ApplicationByClientID", err)
return
}
grant, err := app.CreateGrant(ctx.User.ID, form.Scope)
if err != nil {
handleAuthorizeError(ctx, AuthorizeError{
State: form.State,
ErrorDescription: "cannot create grant for user",
ErrorCode: ErrorCodeServerError,
}, form.RedirectURI)
return
}
if len(form.Nonce) > 0 {
err := grant.SetNonce(form.Nonce)
if err != nil {
log.Error("Unable to update nonce: %v", err)
}
}
var codeChallenge, codeChallengeMethod string
codeChallenge, _ = ctx.Session.Get("CodeChallenge").(string)
codeChallengeMethod, _ = ctx.Session.Get("CodeChallengeMethod").(string)
code, err := grant.GenerateNewAuthorizationCode(form.RedirectURI, codeChallenge, codeChallengeMethod)
if err != nil {
handleServerError(ctx, form.State, form.RedirectURI)
return
}
redirect, err := code.GenerateRedirectURI(form.State)
if err != nil {
handleServerError(ctx, form.State, form.RedirectURI)
return
}
ctx.Redirect(redirect.String(), 302)
}
// OIDCWellKnown generates JSON so OIDC clients know Gitea's capabilities
func OIDCWellKnown(ctx *context.Context) {
t := ctx.Render.TemplateLookup("user/auth/oidc_wellknown")
ctx.Resp.Header().Set("Content-Type", "application/json")
ctx.Data["SigningKey"] = oauth2.DefaultSigningKey
if err := t.Execute(ctx.Resp, ctx.Data); err != nil {
log.Error("%v", err)
ctx.Error(http.StatusInternalServerError)
}
}
// OIDCKeys generates the JSON Web Key Set
func OIDCKeys(ctx *context.Context) {
jwk, err := oauth2.DefaultSigningKey.ToJWK()
if err != nil {
log.Error("Error converting signing key to JWK: %v", err)
ctx.Error(http.StatusInternalServerError)
return
}
jwk["use"] = "sig"
jwks := map[string][]map[string]string{
"keys": {
jwk,
},
}
ctx.Resp.Header().Set("Content-Type", "application/json")
enc := json.NewEncoder(ctx.Resp)
if err := enc.Encode(jwks); err != nil {
log.Error("Failed to encode representation as json. Error: %v", err)
}
}
// AccessTokenOAuth manages all access token requests by the client
func AccessTokenOAuth(ctx *context.Context) {
form := *web.GetForm(ctx).(*forms.AccessTokenForm)
if form.ClientID == "" {
authHeader := ctx.Req.Header.Get("Authorization")
authContent := strings.SplitN(authHeader, " ", 2)
if len(authContent) == 2 && authContent[0] == "Basic" {
payload, err := base64.StdEncoding.DecodeString(authContent[1])
if err != nil {
handleAccessTokenError(ctx, AccessTokenError{
ErrorCode: AccessTokenErrorCodeInvalidRequest,
ErrorDescription: "cannot parse basic auth header",
})
return
}
pair := strings.SplitN(string(payload), ":", 2)
if len(pair) != 2 {
handleAccessTokenError(ctx, AccessTokenError{
ErrorCode: AccessTokenErrorCodeInvalidRequest,
ErrorDescription: "cannot parse basic auth header",
})
return
}
form.ClientID = pair[0]
form.ClientSecret = pair[1]
}
}
serverKey := oauth2.DefaultSigningKey
clientKey := serverKey
if serverKey.IsSymmetric() {
var err error
clientKey, err = oauth2.CreateJWTSigningKey(serverKey.SigningMethod().Alg(), []byte(form.ClientSecret))
if err != nil {
handleAccessTokenError(ctx, AccessTokenError{
ErrorCode: AccessTokenErrorCodeInvalidRequest,
ErrorDescription: "Error creating signing key",
})
return
}
}
switch form.GrantType {
case "refresh_token":
handleRefreshToken(ctx, form, serverKey, clientKey)
case "authorization_code":
handleAuthorizationCode(ctx, form, serverKey, clientKey)
default:
handleAccessTokenError(ctx, AccessTokenError{
ErrorCode: AccessTokenErrorCodeUnsupportedGrantType,
ErrorDescription: "Only refresh_token or authorization_code grant type is supported",
})
}
}
func handleRefreshToken(ctx *context.Context, form forms.AccessTokenForm, serverKey, clientKey oauth2.JWTSigningKey) {
token, err := oauth2.ParseToken(form.RefreshToken, serverKey)
if err != nil {
handleAccessTokenError(ctx, AccessTokenError{
ErrorCode: AccessTokenErrorCodeUnauthorizedClient,
ErrorDescription: "client is not authorized",
})
return
}
// get grant before increasing counter
grant, err := models.GetOAuth2GrantByID(token.GrantID)
if err != nil || grant == nil {
handleAccessTokenError(ctx, AccessTokenError{
ErrorCode: AccessTokenErrorCodeInvalidGrant,
ErrorDescription: "grant does not exist",
})
return
}
// check if token got already used
if setting.OAuth2.InvalidateRefreshTokens && (grant.Counter != token.Counter || token.Counter == 0) {
handleAccessTokenError(ctx, AccessTokenError{
ErrorCode: AccessTokenErrorCodeUnauthorizedClient,
ErrorDescription: "token was already used",
})
log.Warn("A client tried to use a refresh token for grant_id = %d was used twice!", grant.ID)
return
}
accessToken, tokenErr := newAccessTokenResponse(grant, serverKey, clientKey)
if tokenErr != nil {
handleAccessTokenError(ctx, *tokenErr)
return
}
ctx.JSON(http.StatusOK, accessToken)
}
func handleAuthorizationCode(ctx *context.Context, form forms.AccessTokenForm, serverKey, clientKey oauth2.JWTSigningKey) {
app, err := models.GetOAuth2ApplicationByClientID(form.ClientID)
if err != nil {
handleAccessTokenError(ctx, AccessTokenError{
ErrorCode: AccessTokenErrorCodeInvalidClient,
ErrorDescription: fmt.Sprintf("cannot load client with client id: '%s'", form.ClientID),
})
return
}
if !app.ValidateClientSecret([]byte(form.ClientSecret)) {
handleAccessTokenError(ctx, AccessTokenError{
ErrorCode: AccessTokenErrorCodeUnauthorizedClient,
ErrorDescription: "client is not authorized",
})
return
}
if form.RedirectURI != "" && !app.ContainsRedirectURI(form.RedirectURI) {
handleAccessTokenError(ctx, AccessTokenError{
ErrorCode: AccessTokenErrorCodeUnauthorizedClient,
ErrorDescription: "client is not authorized",
})
return
}
authorizationCode, err := models.GetOAuth2AuthorizationByCode(form.Code)
if err != nil || authorizationCode == nil {
handleAccessTokenError(ctx, AccessTokenError{
ErrorCode: AccessTokenErrorCodeUnauthorizedClient,
ErrorDescription: "client is not authorized",
})
return
}
// check if code verifier authorizes the client, PKCE support
if !authorizationCode.ValidateCodeChallenge(form.CodeVerifier) {
handleAccessTokenError(ctx, AccessTokenError{
ErrorCode: AccessTokenErrorCodeUnauthorizedClient,
ErrorDescription: "client is not authorized",
})
return
}
// check if granted for this application
if authorizationCode.Grant.ApplicationID != app.ID {
handleAccessTokenError(ctx, AccessTokenError{
ErrorCode: AccessTokenErrorCodeInvalidGrant,
ErrorDescription: "invalid grant",
})
return
}
// remove token from database to deny duplicate usage
if err := authorizationCode.Invalidate(); err != nil {
handleAccessTokenError(ctx, AccessTokenError{
ErrorCode: AccessTokenErrorCodeInvalidRequest,
ErrorDescription: "cannot proceed your request",
})
}
resp, tokenErr := newAccessTokenResponse(authorizationCode.Grant, serverKey, clientKey)
if tokenErr != nil {
handleAccessTokenError(ctx, *tokenErr)
return
}
// send successful response
ctx.JSON(http.StatusOK, resp)
}
func handleAccessTokenError(ctx *context.Context, acErr AccessTokenError) {
ctx.JSON(http.StatusBadRequest, acErr)
}
func handleServerError(ctx *context.Context, state string, redirectURI string) {
handleAuthorizeError(ctx, AuthorizeError{
ErrorCode: ErrorCodeServerError,
ErrorDescription: "A server error occurred",
State: state,
}, redirectURI)
}
func handleAuthorizeError(ctx *context.Context, authErr AuthorizeError, redirectURI string) {
if redirectURI == "" {
log.Warn("Authorization failed: %v", authErr.ErrorDescription)
ctx.Data["Error"] = authErr
ctx.HTML(400, tplGrantError)
return
}
redirect, err := url.Parse(redirectURI)
if err != nil {
ctx.ServerError("url.Parse", err)
return
}
q := redirect.Query()
q.Set("error", string(authErr.ErrorCode))
q.Set("error_description", authErr.ErrorDescription)
q.Set("state", authErr.State)
redirect.RawQuery = q.Encode()
ctx.Redirect(redirect.String(), 302)
}