From: Fabian Keil <fk@fabiankeil.de>
Date: Sat, 8 Feb 2025 12:55:15 +0000 (+0100)
Subject: Look for the "keep-alive" keyword more carefully
X-Git-Url: http://www.privoxy.org/gitweb/@default-cgi@/faq/%22https:/%22javascript:back()/user-manual/documentation.html?a=commitdiff_plain;h=d34d4df1ee741844a53c2bfaf36b5f60fd165e62;p=privoxy.git

Look for the "keep-alive" keyword more carefully

... in Connection headers. Previously connections were not
kept alive if the Connection header contained additional
keywords like "Upgrade".
---

diff --git a/parsers.c b/parsers.c
index a14f970d..5428a445 100644
--- a/parsers.c
+++ b/parsers.c
@@ -1791,6 +1791,51 @@ static jb_err filter_header(struct client_state *csp, char **header)
 }
 
 
+/*********************************************************************
+ *
+ * Function    :  connection_header_contains_keep_alive_keyword
+ *
+ * Description :  Checks wether or not a Connection header contains
+ *                the keep-alive keyword.
+ *
+ * Parameters  :
+ *          1  :  header = The Connection header to check.
+ *
+ * Returns     :  TRUE or FALSE.
+ *
+ *********************************************************************/
+static int connection_header_contains_keep_alive_keyword(const char *header)
+{
+   char *header_content;
+   char *keywords[4];
+   int segments;
+   int keep_alive_keyword_present = FALSE;
+
+   header_content = strdup(header+11);
+   if (header_content == NULL)
+   {
+      log_error(LOG_LEVEL_ERROR,
+         "Out of memory while looking for keep-alive keyword in %s", header);
+      return FALSE;
+   }
+
+   segments = ssplit(header_content, " ,", keywords, SZ(keywords));
+   while (segments-- > 0)
+   {
+      if (!strcmpic(keywords[segments], "keep-alive"))
+      {
+         keep_alive_keyword_present = TRUE;
+         break;
+      }
+   }
+
+   freez(header_content);
+
+   return keep_alive_keyword_present;
+
+}
+
+
 /*********************************************************************
  *
  * Function    :  server_connection
@@ -1811,7 +1856,7 @@ static jb_err filter_header(struct client_state *csp, char **header)
  *********************************************************************/
 static jb_err server_connection(struct client_state *csp, char **header)
 {
-   if (!strcmpic(*header, "Connection: keep-alive")
+   if (connection_header_contains_keep_alive_keyword(*header)
 #ifdef FEATURE_CONNECTION_KEEP_ALIVE
     && !(csp->flags & CSP_FLAG_SERVER_SOCKET_TAINTED)
 #endif