topic Re: cgiwrap problems, is there an 8 character limit for usernames? in Operating System - Linux

cgiwrap problems, is there an 8 character limit for usernames?

Dave Falloon — Mon, 12 Jan 2004 19:24:20 GMT

Hi Guys,

Its been a while but I've run into a weird problem, I have a bunch of vhosts on a machine running:

-apache 1.3.20
-cgiwrap 3.7

The problem I have is that some users get the familiar error,"premature end of script headers" when they try to run cgi scripts via cgi-wrap. If I take their script and copy it to my own users (dave) virtual hosted cgi dir, I can run the script no problem, copy it back and chown it back to the other user "victorian" and it fails to run. When I run the cgiwrapd to debug it I get no output and no errors. I am just grasping at straws right now but I think it may be related to the number of chars in the username. I seem to recall an apache bug of the same type, perhaps cgiwrap has the same thing?

Anyways any help would be appreciated.

Dave

Re: cgiwrap problems, is there an 8 character limit for usernames?

Stuart Browne — Mon, 12 Jan 2004 19:36:48 GMT

What do you mod_redirect rules look like for the VWS's?

I've got users that are longer than 8chr's and don't have this issue, but using a newer apache (can't recall what version of cgiwrap I'm using off the top of my head).

Re: cgiwrap problems, is there an 8 character limit for usernames?

Dave Falloon — Mon, 12 Jan 2004 20:51:03 GMT

I don't have much experience with mod_rewrite so I'll post the rules that have been defined by default:

RewriteEngine on
RewriteCond %{HTTP_HOST} !^209.5.184.230(:80)?$
RewriteCond %{HTTP_HOST} !^secure.blacksun.ca(:80)?$ [NC]
RewriteRule ^/(.*) http://secure.blacksun.ca/$1 [L,R]
RewriteOptions inherit
AliasMatch ^/~([^/]+)(/(.*))? /home/.sites/70/site4/users/$1/web/$3

I hope this renders properly.

In case it doesn't heres an attachment text file.

thanks,

Dave

Re: cgiwrap problems, is there an 8 character limit for usernames?

Steven E. Protter — Tue, 13 Jan 2004 10:19:54 GMT

I can't figure out why you think usernames may be an issue.

My Red Hat Linux Systems all universally ignore any characters in a username after character 8. Just a note in case you're concerned.

If I create a user called jerusalem (9 char) and then try and log on as that user its real name is jerusale

SEP

Re: cgiwrap problems, is there an 8 character limit for usernames?

Dave Falloon — Tue, 13 Jan 2004 21:37:07 GMT

So this is going to fry your melons out there guys ( it fried mine :) :

I started toying with usernames on this machine, created many many 9 character usernames.

The cgiwrap fails if the ninth character is any one of the following letters:

c, o, n, g, p, w

This is not a prank, and I am at a loss as to why that would happen.

Next thing I tried was a ten character user name that had the ninth character of the user name "o" and it too fails with the dreaded "premature end of script headers"

So I don't know where to go from here. What would cause something so arbitrary?

Thanks guys,

Dave

Re: cgiwrap problems, is there an 8 character limit for usernames?

Stuart Browne — Wed, 14 Jan 2004 22:27:18 GMT

If I had to hazard a guess, I'd say there's more mod rewrite stuff in one of your cnofiguration files, that you've not found.

Re: cgiwrap problems, is there an 8 character limit for usernames?

Elmar P. Kolkman — Thu, 15 Jan 2004 01:37:58 GMT

You might try to create a user with 9 character (or 10) username with a homedirectory that only consists of the first 8 characters of the username. That might work...

(Just a guess, but combining your problem with SEP's note, that might be it...)

Why it is only not allowing those characters, but allowing others, I don't understand. But on most unix systems usernames are limited or truncated after character 8, with some weird side effects... This might be one of them.

Re: cgiwrap problems, is there an 8 character limit for usernames?

Dave Falloon — Thu, 20 Jan 2005 20:24:14 GMT

Turns out the problem was the cgiwrapd code was releasing a variable and then calling it. Fixed the code and voila its working.

--Dave

Re: cgiwrap problems, is there an 8 character limit for usernames?

Dave Falloon — Thu, 20 Jan 2005 20:24:48 GMT

Woops didn't close this with the last comment.