From: Aki Tuomi <aki.tuomi@open-xchange.com>
Date: Wed, 14 Apr 2021 11:12:16 +0000 (+0300)
Subject: lib-oauth2: Improve identifier escaping function
X-Git-Tag: 2.3.14.1~13
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=7a77e070ddb6a67fe7a40118ba3e3f9b6062a7d1;p=thirdparty%2Fdovecot%2Fcore.git

lib-oauth2: Improve identifier escaping function
---

diff --git a/src/lib-oauth2/oauth2-jwt.c b/src/lib-oauth2/oauth2-jwt.c
index 94810766f1..2d46273814 100644
--- a/src/lib-oauth2/oauth2-jwt.c
+++ b/src/lib-oauth2/oauth2-jwt.c
@@ -49,32 +49,31 @@ get_time_field(const struct json_tree *tree, const char *key, long *value_r)
 static const char *escape_identifier(const char *identifier)
 {
 	size_t pos = strcspn(identifier, "./%");
-	if (pos < strlen(identifier)) {
-		/* sanitize identifier, cannot allow dots or / in it, so we
-		  encode them */
-		string_t *new_id = t_str_new(strlen(identifier));
-		/* put initial data */
-		str_append_data(new_id, identifier, pos);
-
-		for (const char *c = identifier+pos; *c != '\0'; c++) {
-			switch (*c) {
-			case '.':
-				str_append(new_id, "%2e");
-				break;
-			case '/':
-				str_append(new_id, "%2f");
-				break;
-			case '%':
-				str_append(new_id, "%25");
-				break;
-			default:
-				str_append_c(new_id, *c);
-				break;
-			}
-		}
-		return str_c(new_id);
+	/* nothing to escape */
+	if (identifier[pos] == '\0')
+		return identifier;
+
+	size_t len = strlen(identifier);
+	string_t *new_id = t_str_new(len);
+	str_append_data(new_id, identifier, pos);
+
+	for (size_t i = pos; i < len; i++) {
+	        switch (identifier[i]) {
+	        case '.':
+	                str_append(new_id, "%2e");
+	                break;
+	        case '/':
+	                str_append(new_id, "%2f");
+	                break;
+	        case '%':
+	                str_append(new_id, "%25");
+	                break;
+	        default:
+	                str_append_c(new_id, identifier[i]);
+	                break;
+	        }
 	}
-	return identifier;
+	return str_c(new_id);
 }
 
 static int