Select Git revision
handlers.go
Frederic BIDON
authored and
Bruno Oliveira da Silva
committed
* abide by modern go linting standards (golangci)
* include `.golangci.yml` config to (optionally) carry out automated linting check on PRs
* does not change behavior
NOTE: upgrading deprecated prometheus middleware is not carried out in this PR
Signed-off-by:
Frederic BIDON <frederic@oneconcern.com>
handlers.go 15.59 KiB
/*
Copyright 2015 All rights reserved.
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/
package main
import (
"bytes"
"encoding/base64"
"encoding/json"
"errors"
"fmt"
"io/ioutil"
"net"
"net/http"
"net/http/pprof"
"net/url"
"path"
"strings"
"time"
"github.com/coreos/go-oidc/oauth2"
"github.com/pressly/chi"
"go.uber.org/zap"
)
// getRedirectionURL returns the redirectionURL for the oauth flow
func (r *oauthProxy) getRedirectionURL(w http.ResponseWriter, req *http.Request) string {
var redirect string
switch r.config.RedirectionURL {
case "":
// need to determine the scheme, cx.Request.URL.Scheme doesn't have it, best way is to default
// and then check for TLS
scheme := unsecureScheme
if req.TLS != nil {
scheme = secureScheme
}
// @QUESTION: should I use the X-Forwarded-<header>?? ..
redirect = fmt.Sprintf("%s://%s",
defaultTo(req.Header.Get("X-Forwarded-Proto"), scheme),
defaultTo(req.Header.Get("X-Forwarded-Host"), req.Host))
default:
redirect = r.config.RedirectionURL
}
state, _ := req.Cookie(requestStateCookie)
if state != nil && req.URL.Query().Get("state") != state.Value {
r.log.Error("state parameter mismatch")
w.WriteHeader(http.StatusForbidden)
return ""
}
return fmt.Sprintf("%s%s", redirect, r.config.WithOAuthURI("callback"))
}
// oauthAuthorizationHandler is responsible for performing the redirection to oauth provider
func (r *oauthProxy) oauthAuthorizationHandler(w http.ResponseWriter, req *http.Request) {
if r.config.SkipTokenVerification {
w.WriteHeader(http.StatusNotAcceptable)
return
}
client, err := r.getOAuthClient(r.getRedirectionURL(w, req))
if err != nil {
r.log.Error("failed to retrieve the oauth client for authorization", zap.Error(err))
w.WriteHeader(http.StatusInternalServerError)
return
}
// step: set the access type of the session
var accessType string
if containedIn("offline", r.config.Scopes) {
accessType = "offline"
}
authURL := client.AuthCodeURL(req.URL.Query().Get("state"), accessType, "")
r.log.Debug("incoming authorization request from client address",
zap.String("access_type", accessType),
zap.String("auth_url", authURL),
zap.String("client_ip", req.RemoteAddr))
// step: if we have a custom sign in page, lets display that
if r.config.hasCustomSignInPage() {
model := make(map[string]string)
model["redirect"] = authURL
w.WriteHeader(http.StatusOK)
_ = r.Render(w, path.Base(r.config.SignInPage), mergeMaps(model, r.config.Tags))
return
}
r.redirectToURL(authURL, w, req, http.StatusTemporaryRedirect)
}
// oauthCallbackHandler is responsible for handling the response from oauth service
func (r *oauthProxy) oauthCallbackHandler(w http.ResponseWriter, req *http.Request) {
if r.config.SkipTokenVerification {
w.WriteHeader(http.StatusNotAcceptable)
return
}
// step: ensure we have a authorization code
code := req.URL.Query().Get("code")
if code == "" {
w.WriteHeader(http.StatusBadRequest)
return
}
client, err := r.getOAuthClient(r.getRedirectionURL(w, req))
if err != nil {
r.log.Error("unable to create a oauth2 client", zap.Error(err))
w.WriteHeader(http.StatusInternalServerError)
return
}
resp, err := exchangeAuthenticationCode(client, code)
if err != nil {
r.log.Error("unable to exchange code for access token", zap.Error(err))
r.accessForbidden(w, req)
return
}
// Flow: once we exchange the authorization code we parse the ID Token; we then check for a access token,
// if a access token is present and we can decode it, we use that as the session token, otherwise we default
// to the ID Token.
token, identity, err := parseToken(resp.IDToken)
if err != nil {
r.log.Error("unable to parse id token for identity", zap.Error(err))
r.accessForbidden(w, req)
return
}
access, id, err := parseToken(resp.AccessToken)
if err == nil {
token = access
identity = id
} else {
r.log.Warn("unable to parse the access token, using id token only", zap.Error(err))
}
// step: check the access token is valid
if err = verifyToken(r.client, token); err != nil {
r.log.Error("unable to verify the id token", zap.Error(err))
r.accessForbidden(w, req)
return
}
accessToken := token.Encode()
// step: are we encrypting the access token?
if r.config.EnableEncryptedToken {
if accessToken, err = encodeText(accessToken, r.config.EncryptionKey); err != nil {
r.log.Error("unable to encode the access token", zap.Error(err))
w.WriteHeader(http.StatusInternalServerError)
return
}
}
r.log.Info("issuing access token for user",
zap.String("email", identity.Email),
zap.String("expires", identity.ExpiresAt.Format(time.RFC3339)),
zap.String("duration", time.Until(identity.ExpiresAt).String()))
// @metric a token has beeb issued
oauthTokensMetric.WithLabelValues("issued").Inc()
// step: does the response has a refresh token and we are NOT ignore refresh tokens?
if r.config.EnableRefreshTokens && resp.RefreshToken != "" {
var encrypted string
encrypted, err = encodeText(resp.RefreshToken, r.config.EncryptionKey)
if err != nil {
r.log.Error("failed to encrypt the refresh token", zap.Error(err))
w.WriteHeader(http.StatusInternalServerError)
return
}
// drop in the access token - cookie expiration = access token
r.dropAccessTokenCookie(req, w, accessToken, r.getAccessCookieExpiration(token, resp.RefreshToken))
switch r.useStore() {
case true:
if err = r.StoreRefreshToken(token, encrypted); err != nil {
r.log.Warn("failed to save the refresh token in the store", zap.Error(err))
}
default:
// notes: not all idp refresh tokens are readable, google for example, so we attempt to decode into
// a jwt and if possible extract the expiration, else we default to 10 days
if _, ident, err := parseToken(resp.RefreshToken); err != nil {
r.dropRefreshTokenCookie(req, w, encrypted, 0)
} else {
r.dropRefreshTokenCookie(req, w, encrypted, time.Until(ident.ExpiresAt))
}
}
} else {
r.dropAccessTokenCookie(req, w, accessToken, time.Until(identity.ExpiresAt))
}
// step: decode the request variable
redirectURI := "/"
if req.URL.Query().Get("state") != "" {
if encodedRequestURI, _ := req.Cookie(requestURICookie); encodedRequestURI != nil {
decoded, _ := base64.StdEncoding.DecodeString(encodedRequestURI.Value)
redirectURI = string(decoded)
}
}
if r.config.BaseURI != "" {
// assuming state starts with slash
redirectURI = r.config.BaseURI + redirectURI
}
r.redirectToURL(redirectURI, w, req, http.StatusTemporaryRedirect)
}
// loginHandler provide's a generic endpoint for clients to perform a user_credentials login to the provider
func (r *oauthProxy) loginHandler(w http.ResponseWriter, req *http.Request) {
errorMsg, code, err := func() (string, int, error) {
if !r.config.EnableLoginHandler {
return "attempt to login when login handler is disabled", http.StatusNotImplemented, errors.New("login handler disabled")
}
username := req.PostFormValue("username")
password := req.PostFormValue("password")
if username == "" || password == "" {
return "request does not have both username and password", http.StatusBadRequest, errors.New("no credentials")
}
client, err := r.client.OAuthClient()
if err != nil {
return "unable to create the oauth client for user_credentials request", http.StatusInternalServerError, err
}
start := time.Now()
token, err := client.UserCredsToken(username, password)
if err != nil {
if strings.HasPrefix(err.Error(), oauth2.ErrorInvalidGrant) {
return "invalid user credentials provided", http.StatusUnauthorized, err
}
return "unable to request the access token via grant_type 'password'", http.StatusInternalServerError, err
}
// @metric observe the time taken for a login request
oauthLatencyMetric.WithLabelValues("login").Observe(time.Since(start).Seconds())
_, identity, err := parseToken(token.AccessToken)
if err != nil {
return "unable to decode the access token", http.StatusNotImplemented, err
}
r.dropAccessTokenCookie(req, w, token.AccessToken, time.Until(identity.ExpiresAt))
// @metric a token has been issued
oauthTokensMetric.WithLabelValues("login").Inc()
w.Header().Set("Content-Type", "application/json")
if err := json.NewEncoder(w).Encode(tokenResponse{
IDToken: token.IDToken,
AccessToken: token.AccessToken,
RefreshToken: token.RefreshToken,
ExpiresIn: token.Expires,
Scope: token.Scope,
}); err != nil {
return "", http.StatusInternalServerError, err
}
return "", http.StatusOK, nil
}()
if err != nil {
r.log.Error(errorMsg,
zap.String("client_ip", req.RemoteAddr),
zap.Error(err))
w.WriteHeader(code)
}
}
// emptyHandler is responsible for doing nothing
func emptyHandler(w http.ResponseWriter, req *http.Request) {}
// logoutHandler performs a logout
// - if it's just a access token, the cookie is deleted
// - if the user has a refresh token, the token is invalidated by the provider
// - optionally, the user can be redirected by to a url
func (r *oauthProxy) logoutHandler(w http.ResponseWriter, req *http.Request) {
// @check if the redirection is there
var redirectURL string
for k := range req.URL.Query() {
if k == "redirect" {
redirectURL = req.URL.Query().Get("redirect")
if redirectURL == "" {
// than we can default to redirection url
redirectURL = strings.TrimSuffix(r.config.RedirectionURL, "/oauth/callback")
}
}
}
// @step: drop the access token
user, err := r.getIdentity(req)
if err != nil {
w.WriteHeader(http.StatusBadRequest)
return
}
// step: can either use the id token or the refresh token
identityToken := user.token.Encode()
if refresh, _, err := r.retrieveRefreshToken(req, user); err == nil {
identityToken = refresh
}
r.clearAllCookies(req, w)
// @metric increment the logout counter
oauthTokensMetric.WithLabelValues("logout").Inc()
// step: check if the user has a state session and if so revoke it
if r.useStore() {
go func() {
if err := r.DeleteRefreshToken(user.token); err != nil {
r.log.Error("unable to remove the refresh token from store", zap.Error(err))
}
}()
}
// set the default revocation url
revokeDefault := ""
if r.idp.EndSessionEndpoint != nil {
revokeDefault = r.idp.EndSessionEndpoint.String()
}
revocationURL := defaultTo(r.config.RevocationEndpoint, revokeDefault)
// @check if we should redirect to the provider
if r.config.EnableLogoutRedirect {
sendTo := fmt.Sprintf("%s/protocol/openid-connect/logout", strings.TrimSuffix(r.config.DiscoveryURL, "/.well-known/openid-configuration"))
// @step: if no redirect uri is set
if redirectURL == "" {
// @step: we first check for a redirection-url and then host header
if r.config.RedirectionURL != "" {
redirectURL = r.config.RedirectionURL
} else {
redirectURL = getRequestHostURL(req)
}
}
r.redirectToURL(fmt.Sprintf("%s?redirect_uri=%s", sendTo, url.QueryEscape(redirectURL)), w, req, http.StatusTemporaryRedirect)
return
}
// step: do we have a revocation endpoint?
if revocationURL != "" {
client, err := r.client.OAuthClient()
if err != nil {
r.log.Error("unable to retrieve the openid client", zap.Error(err))
w.WriteHeader(http.StatusInternalServerError)
return
}
// step: add the authentication headers
encodedID := url.QueryEscape(r.config.ClientID)
encodedSecret := url.QueryEscape(r.config.ClientSecret)
// step: construct the url for revocation
request, err := http.NewRequest(http.MethodPost, revocationURL, bytes.NewBufferString(fmt.Sprintf("refresh_token=%s", identityToken)))
if err != nil {
r.log.Error("unable to construct the revocation request", zap.Error(err))
w.WriteHeader(http.StatusInternalServerError)
return
}
// step: add the authentication headers and content-type
request.SetBasicAuth(encodedID, encodedSecret)
request.Header.Set("Content-Type", "application/x-www-form-urlencoded")
start := time.Now()
response, err := client.HttpClient().Do(request)
if err != nil {
r.log.Error("unable to post to revocation endpoint", zap.Error(err))
return
}
oauthLatencyMetric.WithLabelValues("revocation").Observe(time.Since(start).Seconds())
// step: check the response
switch response.StatusCode {
case http.StatusNoContent:
r.log.Info("successfully logged out of the endpoint", zap.String("email", user.email))
default:
content, _ := ioutil.ReadAll(response.Body)
r.log.Error("invalid response from revocation endpoint",
zap.Int("status", response.StatusCode),
zap.String("response", fmt.Sprintf("%s", content)))
}
}
// step: should we redirect the user
if redirectURL != "" {
r.redirectToURL(redirectURL, w, req, http.StatusTemporaryRedirect)
}
}
// expirationHandler checks if the token has expired
func (r *oauthProxy) expirationHandler(w http.ResponseWriter, req *http.Request) {
user, err := r.getIdentity(req)
if err != nil {
w.WriteHeader(http.StatusUnauthorized)
return
}
if user.isExpired() {
w.WriteHeader(http.StatusUnauthorized)
return
}
w.WriteHeader(http.StatusOK)
}
// tokenHandler display access token to screen
func (r *oauthProxy) tokenHandler(w http.ResponseWriter, req *http.Request) {
user, err := r.getIdentity(req)
if err != nil {
w.WriteHeader(http.StatusBadRequest)
return
}
w.Header().Set("Content-Type", "application/json")
_, _ = w.Write(user.token.Payload)
}
// healthHandler is a health check handler for the service
func (r *oauthProxy) healthHandler(w http.ResponseWriter, req *http.Request) {
w.Header().Set(versionHeader, getVersion())
w.WriteHeader(http.StatusOK)
_, _ = w.Write([]byte("OK\n"))
}
// debugHandler is responsible for providing the pprof
func (r *oauthProxy) debugHandler(w http.ResponseWriter, req *http.Request) {
const symbolProfile = "symbol"
name := chi.URLParam(req, "name")
switch req.Method {
case http.MethodGet:
switch name {
case "heap":
fallthrough
case "goroutine":
fallthrough
case "block":
fallthrough
case "threadcreate":
pprof.Handler(name).ServeHTTP(w, req)
case "cmdline":
pprof.Cmdline(w, req)
case "profile":
pprof.Profile(w, req)
case "trace":
pprof.Trace(w, req)
case symbolProfile:
pprof.Symbol(w, req)
default:
w.WriteHeader(http.StatusNotFound)
}
case http.MethodPost:
switch name {
case symbolProfile:
pprof.Symbol(w, req)
default:
w.WriteHeader(http.StatusNotFound)
}
}
}
// proxyMetricsHandler forwards the request into the prometheus handler
func (r *oauthProxy) proxyMetricsHandler(w http.ResponseWriter, req *http.Request) {
if r.config.LocalhostMetrics {
if !net.ParseIP(realIP(req)).IsLoopback() {
r.accessForbidden(w, req)
return
}
}
r.metricsHandler.ServeHTTP(w, req)
}
// retrieveRefreshToken retrieves the refresh token from store or cookie
func (r *oauthProxy) retrieveRefreshToken(req *http.Request, user *userContext) (token, ecrypted string, err error) {
switch r.useStore() {
case true:
token, err = r.GetRefreshToken(user.token)
default:
token, err = r.getRefreshTokenFromCookie(req)
}
if err != nil {
return
}
ecrypted = token // returns encryped, avoid encoding twice
token, err = decodeText(token, r.config.EncryptionKey)
return
}
func methodNotAllowHandlder(w http.ResponseWriter, req *http.Request) {
w.WriteHeader(http.StatusMethodNotAllowed)
_, _ = w.Write(nil)
}