From 5d96098a82939995dd852380c759771c7c2dd928 Mon Sep 17 00:00:00 2001
From: Michael Boelen <michael.boelen@cisofy.com>
Date: Thu, 8 Jul 2021 14:54:49 +0200
Subject: [PATCH] Switched order for interface detection on Linux

---
 include/functions | 38 +++++++++++++++++++-------------------
 1 file changed, 19 insertions(+), 19 deletions(-)

diff --git a/include/functions b/include/functions
index cdb0c786..f4fc6218 100644
--- a/include/functions
+++ b/include/functions
@@ -990,9 +990,23 @@
                 ;;
 
                 "Linux")
+                    # Try fetching information from /sys in case 'ip' is not available or does not give expected results
+                    if IsEmpty "${FIND}" -a -d /sys/class/net ]; then
+                        NET_INTERFACES=$(${FINDBINARY} /sys/class/net ! -type d -exec realpath {} \; 2> /dev/null | sort | awk -F'/' '!/virtual/ && /devices/ {for (x=1;x<=NF;x++) if ($x~"net") print $(x+1)}')
+                        for INTERFACE in ${NET_INTERFACES}; do
+                            if grep -q -s 'up' "/sys/class/net/${INTERFACE}/operstate"; then
+                                LogText "Interface '${INTERFACE}' is up, fetching MAC address"
+                                FIND=$(head -1 "/sys/class/net/${INTERFACE}/address" | tr '[:upper:]' '[:lower:]')
+                                if HasData "${FIND}"; then
+                                    HOSTID_GEN="linux-sys-interface-up"
+                                    break
+                                fi
+                            fi
+                        done
+                    fi
 
-                    # First try ip, as it is available to most modern Linux distributions
-                    if [ -n "${IPBINARY}" ]; then
+                    # Next is to try ip, as it is available to most modern Linux distributions
+                    if IsEmpty "${FIND}" && [ -n "${IPBINARY}" ]; then
                         LogText "Info: trying output from 'ip' to generate HostID"
                         # Determine if we have the common available eth0 interface. If so, give that priority.
                         # Note: apply sorting in case there would be multiple MAC addresses linked to increase predictable end result
@@ -1022,21 +1036,7 @@
                         fi
                     fi
 
-                    # Try fetching information from /sys in case 'ip' is not available or does not give expected results
-                    if IsEmpty "${FIND}" && [ ${PRIVILEGED} -eq 1 -a -d /sys/class/net ]; then
-                        NET_INTERFACES=$(${FINDBINARY} /sys/class/net ! -type d -exec realpath {} \; 2> /dev/null | sort | awk -F'/' '!/virtual/ && /devices/ {for (x=1;x<=NF;x++) if ($x~"net") print $(x+1)}')
-                        for INTERFACE in ${NET_INTERFACES}; do
-                            if grep -s 'up' "/sys/class/net/${INTERFACE}/operstate"; then
-                                LogText "Interface '${INTERFACE}' is up, fetching MAC address"
-                                FIND=$(head -1 "/sys/class/net/${INTERFACE}/address" | tr '[:upper:]' '[:lower:]')
-                                if HasData "${FIND}"; then
-                                    HOSTID_GEN="linux-sys-interface-up"
-                                    break
-                                fi
-                            fi
-                        done
-                    fi
-
+                    # Finally try ifconfig
                     if IsEmpty "${FIND}" && [ -n "${IFCONFIGBINARY}" ]; then
                         LogText "Info: no information found from 'ip' or in /sys, trying output from 'ifconfig'"
                         # Determine if we have the eth0 interface (not all Linux distributions have this, e.g. Arch)
@@ -1073,9 +1073,9 @@
                         fi
                     fi
 
-                    # Check if we found a HostID
+                    # Check if we found a MAC address to generate the HostID
                     if HasData "${FIND}"; then
-                        LogText "Info: using hardware address ${FIND} to create HostID"
+                        LogText "Info: using hardware address '${FIND}' to create HostID"
                         HOSTID=$(echo ${FIND} | ${SHA1SUMBINARY} | awk '{ print $1 }')
                         LogText "Result: Found HostID: ${HOSTID}"
                     else