clanCore: init machineId and diskId v2

nixosModules/clanCore/uuid4.sh

@@ -0,0 +1,20 @@
+#!/usr/bin/env bash
+
+# Read 16 bytes from /dev/urandom
+uuid=$(dd if=/dev/urandom bs=1 count=16 2>/dev/null | od -An -tx1 | tr -d ' \n')
+
+# Break the UUID into pieces and apply the required modifications
+byte6=${uuid:12:2}
+byte8=${uuid:16:2}
+
+# Construct the correct version and variant
+hex_byte6=$(printf "%x" $((0x$byte6 & 0x0F | 0x40)))
+hex_byte8=$(printf "%x" $((0x$byte8 & 0x3F | 0x80)))
+
+# Rebuild the UUID with the correct fields
+uuid_v4="${uuid:0:12}${hex_byte6}${uuid:14:2}${hex_byte8}${uuid:18:14}"
+
+# Format the UUID correctly 8-4-4-4-12
+uuid_formatted="${uuid_v4:0:8}-${uuid_v4:8:4}-${uuid_v4:12:4}-${uuid_v4:16:4}-${uuid_v4:20:12}"
+
+echo -n "$uuid_formatted"