Avoid loop device naming conflicts with snaps by optaining an available name from the system instead of using a static device name ("/dev/loop0").

setup/ehdd/create_hdd.sh

@@ -1,28 +1,22 @@
 #!/bin/bash
-if [ -s /etc/mailinabox.conf ]; then
-    source /etc/mailinabox.conf
-    [ $? -eq 0 ] || exit 1
-else
-    STORAGE_ROOT="/home/${STORAGE_USER:-user-data}"
-fi
 
-EHDD_IMG="$STORAGE_ROOT.HDD"
-EHDD_SIZE_GB="$1"
-MOUNTPOINT="$STORAGE_ROOT"
+source "setup/ehdd/ehdd_funcs.sh" || exit 1
 
 if [ "$1" == "" ]; then
     echo "usage: $0 <size-in-gb>"
     echo -n "  hdd image location: $EHDD_IMG"
-    if [ -e "$EHDD_IMG" ]; then echo " (exists)"; else echo ""; fi
+    if [ -e "$EHDD_IMG" ]; then echo " (exists!)"; else echo ""; fi
     exit 1
 elif [ "$1" == "-location" ]; then
     echo "$EHDD_IMG"
     exit 0
 elif [ "$1" == "-mountpoint" ]; then
-    echo "$MOUNTPOINT"
+    echo "$EHDD_MOUNTPOINT"
     exit 0
 fi
 
+EHDD_SIZE_GB="$1"
+
 
 if [ ! -e "$EHDD_IMG" ]; then
     echo "Creating ${EHDD_SIZE_GB}G encryped drive: $EHDD_IMG"
@@ -30,19 +24,20 @@ if [ ! -e "$EHDD_IMG" ]; then
     [ $count -eq 0 ] && echo "Invalid size" && exit 1
     apt-get -q=2 -y install cryptsetup || exit 1
     dd if=/dev/zero of="$EHDD_IMG" bs=1M count=$count || exit 1
-    losetup /dev/loop0 "$EHDD_IMG" || exit 1
-    if ! cryptsetup luksFormat -i 15000 /dev/loop0; then
-        losetup -d /dev/loop0
+    loop=$(find_unused_loop)
+    losetup $loop "$EHDD_IMG" || exit 1
+    if ! cryptsetup luksFormat -i 15000 $loop; then
+        losetup -d $loop
         rm -f "$EHDD_IMG"
         exit 1
     fi
     echo ""
     echo "NOTE: You will need to reenter your drive encryption password a number of times"
-    cryptsetup luksOpen /dev/loop0 c1  # map device to /dev/mapper/c1
-    mke2fs -j /dev/mapper/c1
-    cryptsetup luksClose c1
-    losetup -d /dev/loop0
+    cryptsetup luksOpen $loop $EHDD_LUKS_NAME  # map device to /dev/mapper/NAME
+    mke2fs -j /dev/mapper/$EHDD_LUKS_NAME
+    cryptsetup luksClose $EHDD_LUKS_NAME
+    losetup -d $loop
 else
-    echo "$EHDD_IMG already exists..."
+    echo "ERROR: $EHDD_IMG already exists!"
     exit 1
 fi

setup/ehdd/ehdd_funcs.sh

@@ -0,0 +1,20 @@
+
+if [ -s /etc/mailinabox.conf ]; then
+    source /etc/mailinabox.conf
+    [ $? -eq 0 ] || exit 1
+else
+    STORAGE_ROOT="/home/${STORAGE_USER:-user-data}"
+fi
+
+EHDD_IMG="$STORAGE_ROOT.HDD"
+EHDD_MOUNTPOINT="$STORAGE_ROOT"
+EHDD_LUKS_NAME="c1"
+
+
+find_unused_loop() {
+    losetup -f
+}
+
+find_inuse_loop() {
+    losetup -l | awk "\$6 == \"$EHDD_IMG\" { print \$1 }"
+}

setup/ehdd/mount.sh

@@ -1,31 +1,31 @@
 #!/bin/bash
 
-hdd="$(setup/ehdd/create_hdd.sh -location)"
-mountpoint="$(setup/ehdd/create_hdd.sh -mountpoint)"
+. "setup/ehdd/ehdd_funcs.sh" || exit 1
 
-if [ ! -e "$hdd" ]; then
-    echo "NOTE: ecrypted HDD not found at $hdd, not mounting"
+if [ ! -e "$EHDD_IMG" ]; then
+    echo "Warning: ecrypted HDD not found at $EHDD_IMG, not mounting"
     exit 0
 fi
 
-if mount | grep "^/dev/mapper/c1 on $mountpoint" >/dev/null; then
-    echo "$hdd already mounted"
+if mount | grep "^/dev/mapper/$EHDD_LUKS_NAME on $EHDD_MOUNTPOINT" >/dev/null; then
+    echo "$EHDD_IMG already mounted"
     exit 0
 fi
 
-losetup /dev/loop0 "$hdd" || exit 1
-# map device to /dev/mapper/c1
-cryptsetup luksOpen /dev/loop0 c1
+loop=$(find_unused_loop)
+losetup $loop "$EHDD_IMG" || exit 1
+# map device to /dev/mapper/NAME
+cryptsetup luksOpen $loop $EHDD_LUKS_NAME
 code=$?
 if [ $code -ne 0 ]; then
-    echo "luksOpen failed ($code) - is $hdd luks formatted?"
-    losetup -d /dev/loop0
+    echo "luksOpen failed ($code) - is $EHDD_IMG luks formatted?"
+    losetup -d $loop
     exit 1
 fi
 
-if [ ! -e "$mountpoint" ]; then
-   echo "Creating mount point directory: $mountpoint"
-   mkdir -p "$mountpoint" || exit 1
+if [ ! -e "$EHDD_MOUNTPOINT" ]; then
+   echo "Creating mount point directory: $EHDD_MOUNTPOINT"
+   mkdir -p "$EHDD_MOUNTPOINT" || exit 1
 fi
-mount /dev/mapper/c1 "$mountpoint" || exit 1
-echo "Success: mounted $mountpoint"
+mount /dev/mapper/$EHDD_LUKS_NAME "$EHDD_MOUNTPOINT" || exit 1
+echo "Success: mounted $EHDD_MOUNTPOINT"

setup/ehdd/postinstall.sh

@@ -1,6 +1,7 @@
 #!/bin/bash
 
-EHDD_IMG="$(setup/ehdd/create_hdd.sh -location)"
+. "setup/ehdd/ehdd_funcs.sh" || exit 1
+
 if [ -e "$EHDD_IMG" ]; then
     
     if [ -s /etc/mailinabox.conf ]; then

setup/ehdd/umount.sh

@@ -1,11 +1,11 @@
 #!/bin/bash
 
-mountpoint="$(setup/ehdd/create_hdd.sh -mountpoint)"
+. "setup/ehdd/ehdd_funcs.sh" || exit 1
 
-if ! mount | grep "$mountpoint" >/dev/null; then
+if ! mount | grep "$EHDD_MOUNTPOINT" >/dev/null; then
     # not mounted
     exit 0
 fi
-umount "$mountpoint" || exit 1
-cryptsetup luksClose c1
-losetup -d /dev/loop0
+umount "$EHDD_MOUNTPOINT" || exit 1
+cryptsetup luksClose $EHDD_LUKS_NAME
+losetup -d $(find_inuse_loop)