Module: Roda::RodaPlugins::RouteCsrf::InstanceMethods

Defined in:
lib/roda/plugins/route_csrf.rb

Instance Method Summary collapse

Instance Method Details

#check_csrf!(opts = OPTS, &block) ⇒ Object

Check that the submitted CSRF token is valid, if the request requires a CSRF token. If the CSRF token is valid or the request does not require a CSRF token, return nil. Otherwise, if a block is given, treat it as a routing block and yield to it, and if a block is not given, use the :csrf_failure option to determine how to handle it.



182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
# File 'lib/roda/plugins/route_csrf.rb', line 182

def check_csrf!(opts=OPTS, &block)
  if msg = csrf_invalid_message(opts)
    if block
      @_request.on(&block)
    end
    
    case failure_action = opts.fetch(:csrf_failure, csrf_options[:csrf_failure])
    when :raise
      raise InvalidToken, msg
    when :empty_403
      throw :halt, [403, {'Content-Type'=>'text/html', 'Content-Length'=>'0'}, []]
    when :clear_session
      session.clear
    when Proc
      @_request.on{instance_exec(@_request, &failure_action)}
    else
      raise RodaError, "Unsupported :csrf_failure option: #{failure_action.inspect}"
    end
  end
end

#csrf_fieldObject

The name of the hidden input tag containing the CSRF token. Also used as the name for the meta tag.



205
206
207
# File 'lib/roda/plugins/route_csrf.rb', line 205

def csrf_field
  csrf_options[:field]
end

#csrf_headerObject

The HTTP header name to use when submitting CSRF tokens in an HTTP header, if such support is enabled (it is not by default).



211
212
213
# File 'lib/roda/plugins/route_csrf.rb', line 211

def csrf_header
  csrf_options[:header]
end

#csrf_metatagObject

An HTML meta tag string containing a CSRF token that is not request-specific. It is not recommended to use this, as it doesn’t support request-specific tokens.



217
218
219
# File 'lib/roda/plugins/route_csrf.rb', line 217

def csrf_metatag
  "<meta name=\"#{csrf_field}\" content=\"#{csrf_token}\" \/>"
end

#csrf_path(action) ⇒ Object

Given a form action, return the appropriate path to use for the CSRF token. This makes it easier to generate request-specific tokens without having to worry about the different types of form actions (relative paths, absolute paths, URLs, empty paths).



225
226
227
228
229
230
231
232
233
234
235
236
237
# File 'lib/roda/plugins/route_csrf.rb', line 225

def csrf_path(action)
  case action
  when nil, '', /\A[#?]/
    # use current path
    request.path
  when /\A(?:https?:\/)?\//
    # Either full URI or absolute path, extract just the path
    URI.parse(action).path
  else
    # relative path, join to current path
    URI.join(request.url, action).path
  end
end

#csrf_tag(*args) ⇒ Object

An HTML hidden input tag string containing the CSRF token. See csrf_token for arguments.



241
242
243
# File 'lib/roda/plugins/route_csrf.rb', line 241

def csrf_tag(*args)
  "<input type=\"hidden\" name=\"#{csrf_field}\" value=\"#{csrf_token(*args)}\" \/>"
end

#csrf_token(path = nil, method = ('POST' if path)) ⇒ Object

The value of the csrf token. For a path specific token, provide a path argument. By default, it a path is provided, the POST request method will be assumed. To generate a token for a non-POST request method, pass the method as the second argument.



249
250
251
252
253
# File 'lib/roda/plugins/route_csrf.rb', line 249

def csrf_token(path=nil, method=('POST' if path))
  token = SecureRandom.random_bytes(31)
  token << csrf_hmac(token, method, path)
  Base64.strict_encode64(token)
end

#use_request_specific_csrf_tokens?Boolean

Whether request-specific CSRF tokens should be used by default.

Returns:

  • (Boolean)


256
257
258
# File 'lib/roda/plugins/route_csrf.rb', line 256

def use_request_specific_csrf_tokens?
  csrf_options[:require_request_specific_tokens]
end

#valid_csrf?(opts = OPTS) ⇒ Boolean

Whether the submitted CSRF token is valid for the request. True if the request does not require a CSRF token.

Returns:

  • (Boolean)


262
263
264
# File 'lib/roda/plugins/route_csrf.rb', line 262

def valid_csrf?(opts=OPTS)
  csrf_invalid_message(opts).nil?
end