This is AWS WAF Classic documentation. For more information, see
AWS WAF Classic
in the developer guide.
For the latest version of AWS WAF, use the AWS WAFV2 API and see the
AWS WAF Developer Guide.
With the latest version, AWS WAF has a single set of endpoints for
regional and global use.
Inserts or deletes SizeConstraint objects (filters) in a
SizeConstraintSet. For each SizeConstraint
object, you specify the
following values:
Whether to insert or delete the object from the array. If you want
to change a SizeConstraintSetUpdate
object, you delete the
existing object and add a new one.
The part of a web request that you want AWS WAF to evaluate, such as
the length of a query string or the length of the User-Agent
header.
Whether to perform any transformations on the request, such as
converting it to lowercase, before checking its length. Note that
transformations of the request body are not supported because the
AWS resource forwards only the first 8192
bytes of your request to
AWS WAF.
You can only specify a single type of TextTransformation.
A ComparisonOperator
used for evaluating the selected part of the
request against the specified Size
, such as equals, greater than,
less than, and so on.
The length, in bytes, that you want AWS WAF to watch for in selected
part of the request. The length is computed after applying the
transformation.
For example, you can add a SizeConstraintSetUpdate
object that matches
web requests in which the length of the User-Agent
header is greater
than 100 bytes. You can then configure AWS WAF to block those requests.
To create and configure a SizeConstraintSet
, perform the following
steps:
Create a SizeConstraintSet.
For more information, see
create_size_constraint_set
.
Use get_change_token
to get the change
token that you provide in the ChangeToken
parameter of an
update_size_constraint_set
request.
Submit an
update_size_constraint_set
request to specify the part of the request that you want AWS WAF to
inspect (for example, the header or the URI) and the value that you
want AWS WAF to watch for.
For more information about how to use the AWS WAF API to allow or block
HTTP requests, see the AWS WAF Developer Guide.