Merge pull request 'fedora-intune: query Defender through systemd-run instead of a snapshot' (#8) from misthios/defender-query-via-systemd-run into main

Reviewed-on: #8

images/fedora-intune/intune/defender-compliance.sh

@@ -2,20 +2,26 @@
 # Intune custom compliance discovery script for Linux: is Microsoft Defender
 # for Endpoint (mdatp) installed, onboarded, licensed and protecting?
 #
-# Upload in Intune > Devices > Compliance > Scripts (Linux), and pair it with
+# Upload in Intune > Endpoint security > Device compliance > Scripts (Linux),
-# defender-compliance.json in a Linux compliance policy (Custom compliance).
+# and pair it with defender-compliance.json in a Linux compliance policy
-# Himmelblau runs it as root inside himmelblaud-tasks.service and sends the
+# (Custom compliance). Himmelblau runs it as root inside
-# JSON on stdout to Intune, which evaluates it against the rules. Every setting
+# himmelblaud-tasks.service and sends the JSON on stdout to Intune, which
-# is always emitted, so a missing or stopped Defender reads as non-compliant
+# evaluates it against the rules. Every setting is always emitted, so a missing
-# instead of as a script error.
+# or stopped Defender reads as non-compliant instead of as a script error.
 
 MDATP=/usr/bin/mdatp
 
-# Print one `mdatp health` field without quotes or a trailing " [managed]".
+# Defender won't answer `mdatp health` started from inside himmelblaud-tasks
-# Unlicensed or unonboarded, mdatp prints "ATTENTION: ..." lines first.
+# (it can't read that process while checking the caller), so ask through
+# systemd, which runs mdatp as its own child. Elsewhere, ask mdatp directly.
+health="$(systemd-run --quiet --wait --pipe --collect "${MDATP}" health 2>/dev/null)"
+grep -q '^healthy' <<< "${health}" || health="$("${MDATP}" health 2>/dev/null)"
+
+# Print one field of the `mdatp health` output ("name : value") without
+# quotes or a trailing " [managed]".
 field() {
-  "${MDATP}" health --field "$1" 2>/dev/null | grep -v '^ATTENTION' | tail -n1 \
+  grep -m1 "^$1 *:" <<< "${health}" \
-    | sed -e 's/ \[managed\]$//' -e 's/^"//' -e 's/"$//'
+    | sed -e 's/^[^:]*: *//' -e 's/ \[managed\]$//' -e 's/^"//' -e 's/"$//'
 }
 
 bool() {