- ``value {unsigned}``: key value.
+- ``gre_option``: match GRE optional fields(checksum/key/sequence).
+
+ - ``checksum {unsigned}``: checksum value.
+ - ``key {unsigned}``: key value.
+ - ``sequence {unsigned}``: sequence number value.
+
- ``fuzzy``: fuzzy pattern match, expect faster than default.
- ``thresh {unsigned}``: accuracy threshold.