Incorrect handling of "%2b" in rewrite directive

[Maxim Dounin]

Hello!

On Wed, Oct 09, 2013 at 06:54:08PM +0400, Dmitry Petrov wrote:

> Hi.
> 
> To perform rewrite, nginx does ngx_unescape_uri and then ngx_escape_uri to
> pass request to backend. There is a problem with this functions: they both
> can't handler "+" propertly: ngx_escape_uri does not escape «+» character
> 
> So when there is «%2b» sequence in rewrite command, it will be passed to
> backend as «+» where it SHOULD be interpreted as space character.
> I've attached a small patch that solved a problem for me.
> 
> For testing I used
> location /foo {
>   rewrite (.*) $1 break;
>   proxy_pass http://localhost:1234;
> }
> + while true; do nc -l -p 1234; done — to watch what is really send to
> backend by nginx.

The "+" character has a special meaning only in query components.  
It is allowed and has no special meaning in paths.  That is, URLs 
"http://example.com/foo+bar" and "http://example.com/foo%bbar" are 
equivalent.

-- 
Maxim Dounin
http://nginx.org/en/donation.html