Add "Connection: close" to the HTTP request header, which tells HTTP/1.1

servers to close the connection after completion of the response.  This
should be compatible with HTTP/1.0, as HTTP/1.0 allows for custom header
fields which should be ignored if not recognized by the server.  With
some server configurations, the server would keep the connection alive
without this header line (despite the plugin requesting HTTP/1.0),
resulting in the plugin running into either the server's or it's own
timeout (reported by Roman Schliessmeyer and Jesse Morgan via IRC).


git-svn-id: https://nagiosplug.svn.sourceforge.net/svnroot/nagiosplug/nagiosplug/trunk@1759 f882894a-f735-0410-b71e-b25c423dba1c

NEWS

@@ -2,6 +2,8 @@ This file documents the major additions and syntax changes between releases.
 
 1.4.10 or 1.5 ??
 	Fix check_http buffer overflow vulnerability when following HTTP redirects
+	check_http now explicitly asks HTTP/1.1 servers to close the connection
+	  after completion of the response
 	Check_ldaps' guessing which secure method to use (starttls vs. ssl on connect)  
 	  is now deprecated. See --help for further information.
 	Check_disk now calls stat() on all filesystems to check. (Old: only the ones selected using -p) 

plugins/check_http.c

@@ -782,6 +782,9 @@ check_http (void)
 
   asprintf (&buf, "%s %s HTTP/1.0\r\n%s\r\n", http_method, server_url, user_agent);
 
+  /* tell HTTP/1.1 servers not to keep the connection alive */
+  asprintf (&buf, "%sConnection: close\r\n", buf);
+
   /* optionally send the host header info */
   if (host_name)
     asprintf (&buf, "%sHost: %s\r\n", buf, host_name);