feat(webhook-relay): map relayed messages into OCSF, not only custom fields (1.0.1)

The generic mapper now fills the OCSF fields a relayed message has a
place for: metadata.logged_time, log_provider and log_name, the checks
the delivery passed as metadata.labels (relay:hmac…), and raw_data. The
sender's address goes to unmapped.relay.sender_ip rather than
src_endpoint.ip: it is the vendor's cloud, and as an entity it would
correlate every alert of that vendor. metadata.product.name no longer
holds the source id.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Xa1QDbsPTYiVREv2Cvs3Zn

integrations/webhook-relay/mappers/fetch_messages.yaml

@@ -13,6 +13,14 @@ description: |
   falls back to the source. Severity is left to the alert rule's default: a generic
   payload has no scale this mapper could trust.
 
+  The OCSF side carries what has a place in the schema: the relay's message id as the
+  finding uid, the receipt time (time and metadata.logged_time), the source as
+  metadata.log_name, the checks the delivery passed as metadata.labels (relay:hmac…),
+  the payload as raw_data. The sender's address goes to unmapped.relay.sender_ip and
+  NOT src_endpoint.ip: it is the vendor's cloud, and as an entity it would tie every
+  alert of that vendor together.
+
+  The custom fields repeat what layouts and automation conditions read most easily.
   custom:webhook_verified is the trust level: the checks the delivery passed at the
   relay (path_token, header_token, hmac, ip). An alert authenticated by a URL alone
   is plausible, not proven — declare the field and keep destructive automation off
@@ -29,7 +37,26 @@ field_mappings:
   # Key/value rows of the decoded payload's top level, for a table field.
   "custom:webhook_payload": "jsonata: json ? $toTable(json) : body"
 ocsf:
+  # ── Finding ───────────────────────────────────────────────────────
+  # The relay's message id: stable for one delivery. A vendor mapper replaces it with
+  # the vendor's own alert id.
   - { source_path: "id",          ocsf_field: "finding_info.uid" }
   - { source_path: "id",          ocsf_field: "metadata.uid" }
+  # When the relay received it — the best time a payload of unknown shape offers.
+  # A vendor mapper puts the detection's own time in `time` and keeps this one.
   - { source_path: "received_at", ocsf_field: "time" }
-  - { source_path: "source",      ocsf_field: "metadata.product.name" }
+  - { source_path: "received_at", ocsf_field: "metadata.logged_time" }
+  # ── Where it came from ────────────────────────────────────────────
+  - { source_path: "'riposte-relay'", ocsf_field: "metadata.log_provider" }
+  - { source_path: "source",          ocsf_field: "metadata.log_name" }
+  # The checks the delivery passed, as labels: relay:path_token, relay:hmac, relay:ip.
+  # Kept an array even with one check (the singleton trap).
+  - { source_path: "[verified.('relay:' & $)]", ocsf_field: "metadata.labels" }
+  # The payload exactly as sent: what an analyst and the case synthesis read when no
+  # vendor mapper exists yet.
+  - { source_path: "body",        ocsf_field: "raw_data" }
+  # The sender's address is the VENDOR's (its cloud, its collector), never the
+  # attacker's or the victim's: as src_endpoint.ip it would become an entity, and
+  # every alert of that vendor would correlate on it. It stays out of the schema.
+  - { source_path: "remote_ip",   ocsf_field: "unmapped.relay.sender_ip" }
+  - { source_path: "content_type", ocsf_field: "unmapped.relay.content_type" }