From 89bcd1a0c39239cbe74cbaf561bc51d7a1c4e3da Mon Sep 17 00:00:00 2001
From: Livio Amstutz <livio.a@gmail.com>
Date: Mon, 2 Dec 2019 16:15:59 +0100
Subject: [PATCH] error handling

---
 pkg/op/error.go      | 15 ++++++++-------
 pkg/rp/default_rp.go | 14 +++++++++-----
 2 files changed, 17 insertions(+), 12 deletions(-)

diff --git a/pkg/op/error.go b/pkg/op/error.go
index 1f7f70a..5c7da30 100644
--- a/pkg/op/error.go
+++ b/pkg/op/error.go
@@ -2,6 +2,7 @@ package op
 
 import (
 	"net/http"
+	"net/url"
 
 	"github.com/caos/oidc/pkg/oidc"
 	"github.com/caos/oidc/pkg/utils"
@@ -92,20 +93,20 @@ func (e *OAuthError) AuthRequestResponse(w http.ResponseWriter, r *http.Request,
 		http.Error(w, e.Error(), http.StatusBadRequest)
 		return
 	}
-	url := authReq.GetRedirectURI()
+	callback := authReq.GetRedirectURI()
 	if authReq.GetResponseType() == oidc.ResponseTypeCode {
-		url += "?"
+		callback += "?"
 	} else {
-		url += "#"
+		callback += "#"
 	}
-	url += "error=" + string(e.ErrorType)
+	callback += "error=" + string(e.ErrorType)
 	if e.Description != "" {
-		url += "&error_description=" + e.Description
+		callback += "&error_description=" + url.QueryEscape(e.Description)
 	}
 	if authReq.GetState() != "" {
-		url += "&state=" + authReq.GetState()
+		callback += "&state=" + authReq.GetState()
 	}
-	http.Redirect(w, r, url, http.StatusFound)
+	http.Redirect(w, r, callback, http.StatusFound)
 }
 
 func (e *OAuthError) Error() string {
diff --git a/pkg/rp/default_rp.go b/pkg/rp/default_rp.go
index 7c956bb..0537443 100644
--- a/pkg/rp/default_rp.go
+++ b/pkg/rp/default_rp.go
@@ -124,12 +124,16 @@ func (p *DefaultRP) CodeExchangeHandler(callback func(http.ResponseWriter, *http
 			http.Error(w, "failed to get state: "+err.Error(), http.StatusUnauthorized)
 			return
 		}
-		tokens, err := p.CodeExchange(r.Context(), r.URL.Query().Get("code"))
-		if err != nil {
-			http.Error(w, "failed to exchange token: "+err.Error(), http.StatusUnauthorized)
-			return
+		params := r.URL.Query()
+		if params.Get("code") != "" {
+			tokens, err := p.CodeExchange(r.Context(), params.Get("code"))
+			if err != nil {
+				http.Error(w, "failed to exchange token: "+err.Error(), http.StatusUnauthorized)
+				return
+			}
+			callback(w, r, tokens, state)
 		}
-		callback(w, r, tokens, state)
+		w.Write([]byte(params.Get("error")))
 	}
 }