Where is the redirect of urls from uppercase to lowercase in this config?

Question

Nginx

Prompt, please, on a subject.

if ($request_uri ~* "^(.*/)index\.php$") {
        return 301 $1;
    	}
    
  location / {
                try_files       $uri $uri/ @bitrix;
      rewrite ^([^.]*[^/])$ $1/ permanent;
        }

        location ~ \.php$ {
                try_files       $uri @bitrix;
                fastcgi_pass    $php_sock;
                fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name;
               include fastcgi_params;
        }
        location @bitrix {
                fastcgi_pass    $php_sock;
                include fastcgi_params;
                fastcgi_param SCRIPT_FILENAME $document_root/bitrix/urlrewrite.php;
               }
        location ~* /bitrix/admin.+\.php$ {
                try_files       $uri @bitrixadm;
                fastcgi_pass    $php_sock;
                fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name;
                include fastcgi_params;
        }
        location @bitrixadm{
                fastcgi_pass    $php_sock;
                include fastcgi_params;
                fastcgi_param SCRIPT_FILENAME $document_root/bitrix/admin/404.php;
        }

Answer 1

In this config - nowhere. This seems to be what the PHP script does.