id	summary	reporter	owner	description	type	status	priority	milestone	component	version	resolution	keywords	cc	uname	nginx_version
1043	URL encoded change regex match result	David Rousselie		"I am trying to ignore some URL parameters to compute a cache key with this kind of code:
{{{
set $cache_args $args;

if ($cache_args ~ (.*)(?:&|^)utm_source=[^&]*(.*)) {
  set $cache_args $1$2;
}

if ($cache_args ~ (.*)(?:&|^)utm_content=[^&]*(.*)) {
  set $cache_args $1$2;
}
...
}}}

It works until Nginx receive a request with URL encoded chars in its path.
For example, `/%EE?utm_content=1&utm_source=2&arg1=3`:
* The first regex `(.*)(?:&|^)utm_source=[^&]*(.*)` will match but `$2` will be `%26arg1=3` whereas it is `&arg1=3` when there is no chars URL encoded in the path. `$cache_args` is then set to `utm_content=1%26arg1=3`
* Following regex `(.*)(?:&|^)utm_content=[^&]*(.*)` will then match `utm_content=[^&]*` as the whole value `utm_content=1%26arg1=3` instead of just `utm_content=1`. Thus the new value set to `$cache_args` will be empty instead of `&arg1=3`.
"	defect	closed	minor		other	1.10.x	duplicate			Linux cache01-devfe 3.13.0-40-generic #69-Ubuntu SMP Thu Nov 13 17:53:56 UTC 2014 x86_64 x86_64 x86_64 GNU/Linux	"nginx version: nginx/1.10.0
built by gcc 4.8.4 (Ubuntu 4.8.4-2ubuntu1~14.04)
built with OpenSSL 1.0.2h  3 May 2016
TLS SNI support enabled
configure arguments: --prefix=/etc/nginx --sbin-path=/usr/sbin/nginx --modules-path=/usr/lib/nginx/modules --conf-path=/etc/nginx/nginx.conf --error-log-path=/var/log/nginx/error.log --http-log-path=/var/log/nginx/access.log --pid-path=/var/run/nginx.pid --lock-path=/var/run/nginx.lock --http-client-body-temp-path=/var/cache/nginx/client_temp --http-proxy-temp-path=/var/cache/nginx/proxy_temp --http-fastcgi-temp-path=/var/cache/nginx/fastcgi_temp --http-uwsgi-temp-path=/var/cache/nginx/uwsgi_temp --http-scgi-temp-path=/var/cache/nginx/scgi_temp --user=nginx --group=nginx --with-http_ssl_module --with-http_realip_module --with-http_addition_module --with-http_sub_module --with-http_dav_module --with-http_flv_module --with-http_mp4_module --with-http_gunzip_module --with-http_gzip_static_module --with-http_random_index_module --with-http_secure_link_module --with-http_stub_status_module --with-http_auth_request_module --with-http_xslt_module=dynamic --with-http_image_filter_module=dynamic --with-http_geoip_module=dynamic --with-http_perl_module=dynamic --add-dynamic-module=debian/extra/njs-1c50334fbea6/nginx --with-threads --with-stream --with-stream_ssl_module --with-http_slice_module --with-mail --with-mail_ssl_module --with-file-aio --with-ipv6 --add-module=/tmp/ngx_http_enhanced_memcached_module --add-module=/tmp/headers-more-nginx-module --with-openssl=/openssl-1.0.2h --add-module=/tmp/lua-nginx-module --add-module=/tmp/ngx_devel_kit --add-module=/tmp/lua-upstream-nginx-module --with-http_v2_module --with-cc-opt='-g -O2 -fstack-protector --param=ssp-buffer-size=4 -Wformat -Werror=format-security' --with-ld-opt='-Wl,-Bsymbolic-functions -Wl,-z,relro'
"