AWS::WAFv2::RuleGroup JsonBody
Inspect the body of the web request as JSON. The body immediately follows the request headers.
This is used to indicate the web request component to inspect, in the FieldToMatch specification.
Use the specifications in this object to indicate which parts of the JSON body to inspect using the rule's inspection criteria. AWS WAF inspects only the parts of the JSON that result from the matches that you indicate.
Example JSON: "JsonBody": { "MatchPattern": { "All": {} }, "MatchScope": "ALL"
}
Syntax
To declare this entity in your AWS CloudFormation template, use the following syntax:
JSON
{ "InvalidFallbackBehavior" :
String
, "MatchPattern" :JsonMatchPattern
, "MatchScope" :String
, "OversizeHandling" :String
}
YAML
InvalidFallbackBehavior:
String
MatchPattern:JsonMatchPattern
MatchScope:String
OversizeHandling:String
Properties
InvalidFallbackBehavior
-
What AWS WAF should do if it fails to completely parse the JSON body. The options are the following:
-
EVALUATE_AS_STRING
- Inspect the body as plain text. AWS WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string. -
MATCH
- Treat the web request as matching the rule statement. AWS WAF applies the rule action to the request. -
NO_MATCH
- Treat the web request as not matching the rule statement.
If you don't provide this setting, AWS WAF parses and evaluates the content only up to the first parsing failure that it encounters.
AWS WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn't an object or an array.
AWS WAF parses the JSON in the following examples as two valid key, value pairs:
-
Missing comma:
{"key1":"value1""key2":"value2"}
-
Missing colon:
{"key1":"value1","key2""value2"}
-
Extra colons:
{"key1"::"value1","key2""value2"}
Required: No
Type: String
Allowed values:
EVALUATE_AS_STRING | MATCH | NO_MATCH
Update requires: No interruption
-
MatchPattern
-
The patterns to look for in the JSON body. AWS WAF inspects the results of these pattern matches against the rule inspection criteria.
Required: Yes
Type: JsonMatchPattern
Update requires: No interruption
MatchScope
-
The parts of the JSON to match against using the
MatchPattern
. If you specifyAll
, AWS WAF matches against keys and values.Required: Yes
Type: String
Allowed values:
ALL | KEY | VALUE
Update requires: No interruption
OversizeHandling
-
What AWS WAF should do if the body is larger than AWS WAF can inspect. AWS WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to AWS WAF by the underlying host service.
The options for oversize handling are the following:
-
CONTINUE
- Inspect the body normally, according to the rule inspection criteria. -
MATCH
- Treat the web request as matching the rule statement. AWS WAF applies the rule action to the request. -
NO_MATCH
- Treat the web request as not matching the rule statement.
You can combine the
MATCH
orNO_MATCH
settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.Default:
CONTINUE
Required: No
Type: String
Allowed values:
CONTINUE | MATCH | NO_MATCH
Update requires: No interruption
-
Examples
Set the JSON body specification
The following shows an example JSON body field to match specification.
YAML
FieldToMatch: JsonBody: MatchPattern: IncludedPaths: - "/dogs/0/name" - "/cats/0/name" MatchScope: ALL InvalidFallbackBehavior: EVALUATE_AS_STRING OversizeHandling: MATCH
JSON
"FieldToMatch": { "JsonBody": { "MatchPattern": { "IncludedPaths": [ "/dogs/0/name", "/cats/0/name" ] }, "MatchScope": "ALL", "InvalidFallbackBehavior": "EVALUATE_AS_STRING", "OversizeHandling": "MATCH" } }