OPNsense Forum

Archive => 21.1 Legacy Series => Topic started by: gpb on July 09, 2021, 07:17:27 pm

Title: [SOLVED] Cannot log into webui - message 411 Length Required
Post by: gpb on July 09, 2021, 07:17:27 pm

Logging into to the webui, I get in large type the message "411 Length Required" (same in both firefox and chrome).  Thought maybe updating to the hotfix (21.1.8_1) might correct it, but did not.  I restarted the webui and that also did not work.  Checking if lighttpd is running it apparently is as it returns a process ID using pgrep lighttpd.

Any suggestions?

Edit: I can access from an ipad...there's no cert installed there.

Edit: OK, this appears related to Bitdefender, disabling it allows it to work.  Disabling protection on bf and re-enabling solved the problem.

Title: Re: [SOLVED] Cannot log into webui - message 411 Length Required
Post by: gstrauss on October 21, 2021, 07:57:13 am

Glad you identified the actual culprit.

FYI: various gateway protocols (e.g. CGI, FastCGI, SCGI, ...) require CONTENT_LENGTH.  If lighttpd is configured to stream the request body using a non-zero value, e.g.

Code: [Select]

server.stream-request-body = 1, then lighttpd will return "411 Length Required" for requests containing a request body which do not provide Content-Length in the request headers (when lighttpd is required to provide CONTENT_LENGTH to backend protocols).

However, if request body streaming is disabled in lighttpd.conf (the default if not specified)

Code: [Select]

server.stream-request-body = 0, then lighttpd will collect the request body -- by decoding Transfer-Encoding: chunked (HTTP/1.1) or collecting DATA frames (HTTP/2) -- and lighttpd will set CONTENT_LENGTH for the backends.

Therefore, a workaround is to set

Code: [Select]

server.stream-request-body = 0 if intermediaries impolitely modify requests to remove Content-Length.

Title: Re: [SOLVED] Cannot log into webui - message 411 Length Required
Post by: gpb on October 21, 2021, 02:44:30 pm

Good info, thanks.   :)