[squid-users] error:invalid-request HTTP/1.1 (iPhone requesting icloud.com)

Thu Jul 23 05:39:16 UTC 2020

Hi,

some iOS requests to gateway.icloud.com via squid (explicit) throw the 
following error in the logs:

2020-07-23T15:31:08+10:00 00.11.22.68 (squid-1): ABCD::17 (iphoneXs.domain.com) - via -:- - - [23/Jul/2020:15:31:08 +1000] "- error:invalid-request HTTP/1.1" 400 3739 "-" "-" NONE_NONE:HIER _NONE (mode:- sni:-)

Cache file logging of HTTP only shows Squid's response (not the client 
request).

tcpdump gives the following TCP stream (in ASCII):

C->S:
................_\...&_<. at 4..../..K.......' ........z...h.q.B..H..c....0L>...4.......,.+.$.#.
.	...0./.(.'...........=.<.5./.....
..................gateway.icloud.com.....
..............................................h2.http/1.1.......3.&.$... R..{V$_<]..yM..L...1b	..d...).
..-.....+.	..........
.
.........................................................................................................................................................................................................................

S->C:
HTTP/1.1 400 Bad Request
Server: squid/5.0.1-20200312-r8a511d5e0
Mime-Version: 1.0
Date: Thu, 23 Jul 2020 05:00:20 GMT
Content-Type: text/html;charset=utf-8
Content-Length: 3406
X-Squid-Error: ERR_PROTOCOL_UNKNOWN 0
Vary: Accept-Language
Content-Language: en
X-Cache: MISS from proxy-01.thismonkey.com
Connection: close

<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
<html><head>
<meta type="copyright" content="Copyright (C) 1996-2020 The Squid Software Foundation and contributors">
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<title>ERROR: The requested URL could not be retrieved</title>
<style type="text/css"><!-- 

<snip>

Does anyone know what type of request the client is sending?  And why squid is unhappy with it?

To my eye it doesn't look like HTTP - perhaps the h2 is a clue?

Thanks