Note
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.
Creates a SizeConstraintSet
. You then use UpdateSizeConstraintSet to identify the part of a web request that you want AWS WAF to check for length, such as the length of the User-Agent
header or the length of the query string. For example, you can create a SizeConstraintSet
that matches any requests that have a query string that is longer than 100 bytes. You can then configure AWS WAF to reject those requests.
To create and configure a SizeConstraintSet
, perform the following steps:
Use GetChangeToken to get the change token that you provide in the ChangeToken
parameter of a CreateSizeConstraintSet
request.
Submit a CreateSizeConstraintSet
request.
Use GetChangeToken
to get the change token that you provide in the ChangeToken
parameter of an UpdateSizeConstraintSet
request.
Submit an UpdateSizeConstraintSet 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 .
See also: AWS API Documentation
See ‘aws help’ for descriptions of global parameters.
create-size-constraint-set
--name <value>
--change-token <value>
[--cli-input-json | --cli-input-yaml]
[--generate-cli-skeleton <value>]
--name
(string)
A friendly name or description of the SizeConstraintSet . You can’t change
Name
after you create aSizeConstraintSet
.
--change-token
(string)
The value returned by the most recent call to GetChangeToken .
--cli-input-json
| --cli-input-yaml
(string)
Reads arguments from the JSON string provided. The JSON string follows the format provided by --generate-cli-skeleton
. If other arguments are provided on the command line, those values will override the JSON-provided values. It is not possible to pass arbitrary binary values using a JSON-provided value as the string will be taken literally. This may not be specified along with --cli-input-yaml
.
--generate-cli-skeleton
(string)
Prints a JSON skeleton to standard output without sending an API request. If provided with no value or the value input
, prints a sample input JSON that can be used as an argument for --cli-input-json
. Similarly, if provided yaml-input
it will print a sample input YAML that can be used with --cli-input-yaml
. If provided with the value output
, it validates the command inputs and returns a sample output JSON for that command.
See ‘aws help’ for descriptions of global parameters.
SizeConstraintSet -> (structure)
A SizeConstraintSet that contains no
SizeConstraint
objects.SizeConstraintSetId -> (string)
A unique identifier for a
SizeConstraintSet
. You useSizeConstraintSetId
to get information about aSizeConstraintSet
(see GetSizeConstraintSet ), update aSizeConstraintSet
(see UpdateSizeConstraintSet ), insert aSizeConstraintSet
into aRule
or delete one from aRule
(see UpdateRule ), and delete aSizeConstraintSet
from AWS WAF (see DeleteSizeConstraintSet ).
SizeConstraintSetId
is returned by CreateSizeConstraintSet and by ListSizeConstraintSets .Name -> (string)
The name, if any, of the
SizeConstraintSet
.SizeConstraints -> (list)
Specifies the parts of web requests that you want to inspect the size of.
(structure)
Note
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.
Specifies a constraint on the size of a part of the web request. AWS WAF uses the
Size
,ComparisonOperator
, andFieldToMatch
to build an expression in the form of “Size
ComparisonOperator
size in bytes ofFieldToMatch
“. If that expression is true, theSizeConstraint
is considered to match.FieldToMatch -> (structure)
Specifies where in a web request to look for the size constraint.
Type -> (string)
The part of the web request that you want AWS WAF to search for a specified string. Parts of a request that you can search include the following:
HEADER
: A specified request header, for example, the value of theUser-Agent
orReferer
header. If you chooseHEADER
for the type, specify the name of the header inData
.
METHOD
: The HTTP method, which indicated the type of operation that the request is asking the origin to perform. Amazon CloudFront supports the following methods:DELETE
,GET
,HEAD
,OPTIONS
,PATCH
,POST
, andPUT
.
QUERY_STRING
: A query string, which is the part of a URL that appears after a?
character, if any.
URI
: The part of a web request that identifies a resource, for example,/images/daily-ad.jpg
.
BODY
: The part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form. The request body immediately follows the request headers. Note that only the first8192
bytes of the request body are forwarded to AWS WAF for inspection. To allow or block requests based on the length of the body, you can create a size constraint set. For more information, see CreateSizeConstraintSet .
SINGLE_QUERY_ARG
: The parameter in the query string that you will inspect, such as UserName or SalesRegion . The maximum length forSINGLE_QUERY_ARG
is 30 characters.
ALL_QUERY_ARGS
: Similar toSINGLE_QUERY_ARG
, but rather than inspecting a single parameter, AWS WAF will inspect all parameters within the query for the value or regex pattern that you specify inTargetString
.Data -> (string)
When the value of
Type
isHEADER
, enter the name of the header that you want AWS WAF to search, for example,User-Agent
orReferer
. The name of the header is not case sensitive.When the value of
Type
isSINGLE_QUERY_ARG
, enter the name of the parameter that you want AWS WAF to search, for example,UserName
orSalesRegion
. The parameter name is not case sensitive.If the value of
Type
is any other value, omitData
.TextTransformation -> (string)
Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass AWS WAF. If you specify a transformation, AWS WAF performs the transformation on
FieldToMatch
before inspecting it for a match.You can only specify a single type of TextTransformation.
Note that if you choose
BODY
for the value ofType
, you must chooseNONE
forTextTransformation
because CloudFront forwards only the first 8192 bytes for inspection.NONE
Specify
NONE
if you don’t want to perform any text transformations.CMD_LINE
When you’re concerned that attackers are injecting an operating system command line command and using unusual formatting to disguise some or all of the command, use this option to perform the following transformations:
Delete the following characters: ” ‘ ^
Delete spaces before the following characters: / (
Replace the following characters with a space: , ;
Replace multiple spaces with one space
Convert uppercase letters (A-Z) to lowercase (a-z)
COMPRESS_WHITE_SPACE
Use this option to replace the following characters with a space character (decimal 32):
f, formfeed, decimal 12
t, tab, decimal 9
n, newline, decimal 10
r, carriage return, decimal 13
v, vertical tab, decimal 11
non-breaking space, decimal 160
COMPRESS_WHITE_SPACE
also replaces multiple spaces with one space.HTML_ENTITY_DECODE
Use this option to replace HTML-encoded characters with unencoded characters.
HTML_ENTITY_DECODE
performs the following operations:
Replaces
(ampersand)quot;
with"
Replaces
(ampersand)nbsp;
with a non-breaking space, decimal 160Replaces
(ampersand)lt;
with a “less than” symbolReplaces
(ampersand)gt;
with>
Replaces characters that are represented in hexadecimal format,
(ampersand)#xhhhh;
, with the corresponding charactersReplaces characters that are represented in decimal format,
(ampersand)#nnnn;
, with the corresponding charactersLOWERCASE
Use this option to convert uppercase letters (A-Z) to lowercase (a-z).
URL_DECODE
Use this option to decode a URL-encoded value.
ComparisonOperator -> (string)
The type of comparison you want AWS WAF to perform. AWS WAF uses this in combination with the provided
Size
andFieldToMatch
to build an expression in the form of “Size
ComparisonOperator
size in bytes ofFieldToMatch
“. If that expression is true, theSizeConstraint
is considered to match.EQ : Used to test if the
Size
is equal to the size of theFieldToMatch
NE : Used to test if the
Size
is not equal to the size of theFieldToMatch
LE : Used to test if the
Size
is less than or equal to the size of theFieldToMatch
LT : Used to test if the
Size
is strictly less than the size of theFieldToMatch
GE : Used to test if the
Size
is greater than or equal to the size of theFieldToMatch
GT : Used to test if the
Size
is strictly greater than the size of theFieldToMatch
Size -> (long)
The size in bytes that you want AWS WAF to compare against the size of the specified
FieldToMatch
. AWS WAF uses this in combination withComparisonOperator
andFieldToMatch
to build an expression in the form of “Size
ComparisonOperator
size in bytes ofFieldToMatch
“. If that expression is true, theSizeConstraint
is considered to match.Valid values for size are 0 - 21474836480 bytes (0 - 20 GB).
If you specify
URI
for the value ofType
, the / in the URI counts as one character. For example, the URI/logo.jpg
is nine characters long.
ChangeToken -> (string)
The
ChangeToken
that you used to submit theCreateSizeConstraintSet
request. You can also use this value to query the status of the request. For more information, see GetChangeTokenStatus .