Values.FieldToMatchSourceSpecifies a web request component to be used in a rule match statement or in a logging configuration. In a rule statement, this is the part of the web request that you want 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" } } In a logging configuration, this is used in the RedactedFields property to specify a field to redact from the logging records. For this use case, note the following: Even though all FieldToMatch settings are available, the only valid settings for field redaction are UriPath, QueryString, SingleHeader, and Method. In this documentation, the descriptions of the individual fields talk about specifying the web request component to inspect, but for field redaction, you are specifying the component type to redact from the logs. If you have request sampling enabled, the redacted fields configuration for logging has no impact on sampling. You can only exclude fields from request sampling by disabling sampling in the web ACL visibility configuration or by configuring data protection for the web ACL.
type nonrec t = {singleHeader : SingleHeader.t option;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.
*)singleQueryArgument : SingleQueryArgument.t option;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" }
*)allQueryArguments : AllQueryArguments.t option;Inspect all query arguments.
*)uriPath : UriPath.t option;Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg.
*)queryString : QueryString.t option;Inspect the query string. This is the part of a URL that appears after a ? character, if any.
*)body : Body.t option;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. WAF does not support inspecting the entire contents of the web request body if the body exceeds the limit for the resource type. When a web request body is larger than the limit, the underlying host service only forwards the contents that are within the limit to WAF for inspection. For Application Load Balancer and AppSync, the limit is fixed at 8 KB (8,192 bytes). For CloudFront, API Gateway, Amazon Cognito, App Runner, and Verified Access, the default limit is 16 KB (16,384 bytes), and you can increase the limit for each resource type in the web ACL AssociationConfig, for additional processing fees. For Amplify, use the CloudFront limit. For information about how to handle oversized request bodies, see the Body object configuration.
*)method_ : Method.t option;Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.
*)jsonBody : JsonBody.t option;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. WAF does not support inspecting the entire contents of the web request body if the body exceeds the limit for the resource type. When a web request body is larger than the limit, the underlying host service only forwards the contents that are within the limit to WAF for inspection. For Application Load Balancer and AppSync, the limit is fixed at 8 KB (8,192 bytes). For CloudFront, API Gateway, Amazon Cognito, App Runner, and Verified Access, the default limit is 16 KB (16,384 bytes), and you can increase the limit for each resource type in the web ACL AssociationConfig, for additional processing fees. For Amplify, use the CloudFront limit. For information about how to handle oversized request bodies, see the JsonBody object configuration.
*)headers : Headers.t option;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 WAF inspects. Only the first 8 KB (8192 bytes) of a request's headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.
*)headerOrder : HeaderOrder.t option;Inspect a string containing the list of the request's header names, ordered as they appear in the web request that WAF receives for inspection. WAF generates the string and then uses that as the field to match component in its inspection. WAF separates the header names in the string using colons and no added spaces, for example host:user-agent:accept:authorization:referer.
*)jA3Fingerprint : JA3Fingerprint.t option;Available for use with Amazon CloudFront distributions and Application Load Balancers. 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. 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. 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 WAF is able to calculate the fingerprint, it includes it in the logs. For information about the logging fields, see Log fields in the 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.
*)jA4Fingerprint : JA4Fingerprint.t option;Available for use with Amazon CloudFront distributions and Application Load Balancers. Match against the request's JA4 fingerprint. The JA4 fingerprint is a 36-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. 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. You can use this choice only with a string match ByteMatchStatement with the PositionalConstraint set to EXACTLY. You can obtain the JA4 fingerprint for client requests from the web ACL logs. If WAF is able to calculate the fingerprint, it includes it in the logs. For information about the logging fields, see Log fields in the WAF Developer Guide. Provide the JA4 fingerprint string from the logs in your string match statement specification, to match with any future requests that have the same TLS configuration.
*)uriFragment : UriFragment.t option;Inspect fragments of the request URI. You must configure scope and pattern matching filters in the UriFragment object, to define the fragment of a URI that WAF inspects. Only the first 8 KB (8192 bytes) of a request's URI fragments and only the first 200 URI fragments are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize URI fragment content in the UriFragment object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.
*)}val make :
?singleHeader:??? ->
?singleQueryArgument:??? ->
?allQueryArguments:??? ->
?uriPath:??? ->
?queryString:??? ->
?body:??? ->
?method_:??? ->
?jsonBody:??? ->
?headers:??? ->
?cookies:??? ->
?headerOrder:??? ->
?jA3Fingerprint:??? ->
?jA4Fingerprint:??? ->
?uriFragment:??? ->
unit ->
tval to_value :
t ->
[> `Structure of
(string
* [> `Structure of
(string
* [> `Enum of string
| `String of FieldToMatchData.t
| `Structure of
(string
* [> `List of [> `String of JsonPointerPath.t ] list
| `Structure of 'a list ])
list ])
list ])
list ]