Parse header of ${DIGEST_FILE} to set correct hash calculator

hashboot.sh

@@ -16,6 +16,7 @@ HASHER=""
 BOOT_MOUNTED=0
 CONFIG_FILE="/etc/hashboot.cfg"
 
+
 #Umount /boot if we mounted it, exit with given exit code
 function die
 {
@@ -28,13 +29,22 @@ function die
     exit ${1}
 }
 
-
 #If we're not root: exit
 if [ ${UID} -ne 0 ]
 then
     die 4 "You have to be root"
 fi
 
+#If /boot is in fstab but not mounted: mount, mark as mounted
+if grep -q '/boot.*noauto' /etc/fstab && ! grep -q /boot /etc/mtab
+then
+    mount /boot
+    BOOT_MOUNTED=1
+fi
+
+
+if [ "${1}" == "index" ]
+then
     #Try different hashers, use the most secure
     HASHER=$(/usr/bin/which --skip-dot sha512sum 2> /dev/null)
     test -z ${HASHER} && HASHER=$(/usr/bin/which --skip-dot sha384sum 2> /dev/null)
@@ -46,15 +56,6 @@ test -z ${HASHER} && HASHER=$(/usr/bin/which --skip-dot md5sum 2> /dev/null)
     #If we found no hasher: exit
     [ -z ${HASHER} ] && die 5 "No hash calculator found"
 
-#If /boot is in fstab but not mounted: mount, mark as mounted
-if grep -q '/boot.*noauto' /etc/fstab && ! grep -q /boot /etc/mtab
-then
-    mount /boot
-    BOOT_MOUNTED=1
-fi
-
-if [ "${1}" == "index" ]
-then
     #Look for config file and set ${MBR_DEVICE}.
     if [ -f ${CONFIG_FILE} ]
     then
@@ -74,7 +75,7 @@ then
     #Write MBR of MBR_DEVICE to ${DIGEST_FILE}
     dd if=${MBR_DEVICE} of=${MBR_TMP} bs=1M count=1 status=none || die 8
     #Write hashes of all regular files to ${DIGEST_FILE}
-    ${HASHER} ${MBR_TMP} > ${DIGEST_FILE}
+    ${HASHER} ${MBR_TMP} >> ${DIGEST_FILE}
     find /boot -type f -exec ${HASHER} --binary {} >> ${DIGEST_FILE} +
     if [ $? == 0 ]
     then
@@ -94,6 +95,8 @@ then
 elif [ "${1}" == "check" ]
 then
     COUNTER=0
+    HASHER=$(head -n1 ${DIGEST_FILE} | awk '{print $5}')
+
     dd if=${MBR_DEVICE} of=${MBR_TMP} bs=1M count=1 status=none  || die 8
     if $(grep ${MBR_TMP} ${DIGEST_FILE} | ${HASHER} --check --warn --quiet --strict > ${LOG_FILE})
     then