FieldToMatch

The part of the web request that you want AWS WAF to inspect. Include the single FieldToMatch type that you want to inspect, with additional specifications as needed, according to the type. You specify a single request component in FieldToMatch for each rule statement that requires it. To inspect more than one component of the web request, create a separate rule statement for each component.

Example JSON for a QueryString field to match:

"FieldToMatch": { "QueryString": {} }

Example JSON for a Method field to match specification:

"FieldToMatch": { "Method": { "Name": "DELETE" } }

AllQueryArguments

Inspect all query arguments.

Type: AllQueryArguments object

Required: No

Body

Inspect the request body as plain text. The request body immediately follows the request headers. This is 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.

A limited amount of the request body is forwarded to AWS WAF for inspection by the underlying host service. For regional resources, the limit is 8 KB (8,192 bytes) and for CloudFront distributions, the limit is 16 KB (16,384 bytes). For CloudFront distributions, you can increase the limit in the web ACL's AssociationConfig, for additional processing fees.

For information about how to handle oversized request bodies, see the Body object configuration.

Type: Body object

Required: No

Cookies

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that AWS WAF inspects.

Only the first 8 KB (8192 bytes) of a request's cookies and only the first 200 cookies are forwarded to AWS WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. AWS WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

Type: Cookies object

Required: No

HeaderOrder

Inspect a string containing the list of the request's header names, ordered as they appear in the web request that AWS WAF receives for inspection. AWS WAF generates the string and then uses that as the field to match component in its inspection. AWS WAF separates the header names in the string using colons and no added spaces, for example host:user-agent:accept:authorization:referer.

Type: HeaderOrder object

Required: No

Headers

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that AWS WAF inspects.

Only the first 8 KB (8192 bytes) of a request's headers and only the first 200 headers are forwarded to AWS WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. AWS WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

Type: Headers object

Required: No

JA3Fingerprint

Match against the request's JA3 fingerprint. The JA3 fingerprint is a 32-character hash derived from the TLS Client Hello of an incoming request. This fingerprint serves as a unique identifier for the client's TLS configuration. AWS WAF calculates and logs this fingerprint for each request that has enough TLS Client Hello information for the calculation. Almost all web requests include this information.

Note

You can use this choice only with a string match ByteMatchStatement with the PositionalConstraint set to EXACTLY.

You can obtain the JA3 fingerprint for client requests from the web ACL logs. If AWS WAF is able to calculate the fingerprint, it includes it in the logs. For information about the logging fields, see Log fields in the AWS WAF Developer Guide.

Provide the JA3 fingerprint string from the logs in your string match statement specification, to match with any future requests that have the same TLS configuration.

Type: JA3Fingerprint object

Required: No

JsonBody

Inspect the request body as JSON. The request body immediately follows the request headers. This is 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.

For information about how to handle oversized request bodies, see the JsonBody object configuration.

Type: JsonBody object

Required: No

Method

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

Type: Method object

Required: No

QueryString

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Type: QueryString object

Required: No

SingleHeader

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer. This setting isn't case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Type: SingleHeader object

Required: No

SingleQueryArgument

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion. The name can be up to 30 characters long and isn't case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Type: SingleQueryArgument object

Required: No

UriPath

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg.

Type: UriPath object

Required: No

FieldToMatch

Contents

Note

See Also