[Filebeat] improve logic for network.direction in sophos xg fileset (e…

…lastic#22973)

* improve logic for network.direction in sophos xg fileset

- "external" when traffic src and dst are in 'WAN' zone

Relates elastic#21674

* Update CHANGELOG.next.asciidoc

Co-authored-by: Andrew Kroh <andrew.kroh@elastic.co>

Co-authored-by: Andrew Kroh <andrew.kroh@elastic.co>
(cherry picked from commit db4830b)

CHANGELOG.next.asciidoc

@@ -470,6 +470,7 @@ https://github.com/elastic/beats/compare/v7.0.0-alpha2...master[Check the HEAD d
 - Improve panw ECS url fields mapping. {pull}22481[22481]
 - Improve Nats filebeat dashboard. {pull}22726[22726]
 - Add support for UNIX datagram sockets in `unix` input. {issues}18632[18632] {pull}22699[22699]
+- Add logic for external network.direction in sophos xg fileset {pull}22973[22973]
 
 *Heartbeat*
 
@@ -610,4 +611,3 @@ port. {pull}19209[19209]
 
 
 
-

x-pack/filebeat/module/sophos/xg/ingest/firewall.yml

@@ -390,6 +390,10 @@ processors:
     field: network.direction
     value: internal
     if: "['LAN', 'DMZ', 'VPN', 'WiFi'].contains(ctx?.observer?.ingress?.zone) && ['LAN', 'DMZ', 'VPN', 'WiFi'].contains(ctx?.observer?.egress?.zone)"
+- set:
+    field: network.direction
+    value: external
+    if: "ctx?.observer?.ingress?.zone == 'WAN' && ctx?.observer?.egress?.zone == 'WAN'"
 
 #########################
 ## ECS Related Mapping ##