NAME Plack::Middleware::CSRFBlock - CSRF are never propageted to app SYNOPSIS use Plack::Builder; my $app = sub { ... } builder { enable 'Session'; enable 'CSRFBlock'; $app; } DESCRIPTION This middleware blocks CSRF. You can use this middleware without any modifications to your application, in most cases. Here is the strategy: output filter When the application response content-type is "text/html" or "application/xhtml+xml", this inserts hidden input tag that contains token string into "form"s in the response body. For example, the application response body is: input form
this becomes: input form
This affects "form" tags with "method="post"", case insensitive. input check For every POST requests, this module checks input parameters contain the collect token parameter. If not found, throws 403 Forbidden by default. Supports "application/x-www-form-urlencoded" and "multipart/form-data". OPTIONS parameter_name (default:"SEC") Name of the input tag for the token. token_length (default:16); Length of the token string. Max value is 40. session_key (default:"csrfblock.token") This middleware uses Plack::Middleware::Session for token storage. this is the session key for that. blocked (default:403 response) The application called when CSRF is detected. Note: This application can read posted data, but DO NOT use them! onetime (default:FALSE) If this is true, this middleware uses onetime token, that is, whenever client sent collect token and this middleware detect that, token string is regenerated. This makes your applications more secure, but in many cases, is too strict. CAVEATS This middleware doesn't work with pure Ajax POST request, because it cannot insert the token parameter to the request. We suggest, for example, to use jQuery Form Plugin like:
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