support non-standard SSH ports, fix some shellchecks

hosts.csv.sample

@@ -2,5 +2,5 @@
 # SPDX-License-Identifier: CC0-1.0
 
 # Username@Hostname; Path1 | Path2 | Path3; Uberspace version (default = 7)
-root@server; /home
 user@host.uberspace.de; %virtual | %mysql | /home/user/service
+root@server:2222; /home

ssh-checker.sh

@@ -2,11 +2,11 @@
 #  SPDX-FileCopyrightText: 2019 Max Mehl <mail [at] mehl [dot] mx>
 #  SPDX-License-Identifier: GPL-3.0-or-later
 ########################################################################
-#  
-#  Reads hosts file and checks SSH access. If not possible with public 
-#  key, this script tries to place the system's public key on the host 
-#  via a normal (password-based) SSH access attempt. 
-#  
+#
+#  Reads hosts file and checks SSH access. If not possible with public
+#  key, this script tries to place the system's public key on the host
+#  via a normal (password-based) SSH access attempt.
+#
 ########################################################################
 
 CURDIR=$(dirname "$(readlink -f "$0")")
@@ -15,7 +15,7 @@ source "$CURDIR"/config.cfg
 
 if [ ! -e "${HOSTS}" ]; then echo "Missing hosts file. Please set a correct value of HOSTS= in your config file. Current value: ${HOSTS}"; exit 1; fi
 
-if [ ! -z "${SSH_KEY}" ]; then
+if [ -n "${SSH_KEY}" ]; then
   SSH_KEY_ARG="-i ${SSH_KEY}"
 else
   # defaults
@@ -29,19 +29,31 @@ function trim {
   sed -r -e 's/^\s*//g' -e 's/\s*$//g'
 }
 
-while read line; do
+while read -r line; do
   # if line is a comment, go to next line
-  if $(echo "$line" | grep -qE "^\s*#"); then continue; fi
+  if echo "$line" | grep -qE "^\s*#"; then continue; fi
 
   RHOST=$(echo "$line" | cut -d";" -f1 | trim)
 
+  # Jump to next line if this line's host does not match host of ARG1 (if given)
   if [[ "${ARG1}" != "" ]] && [[ "${ARG1}" != "${RHOST}" ]]; then
     continue
   fi
-  
+
+  # Get SSH port if needed
+  if echo "$RHOST" | grep -q ":"; then
+    RPORT=$(echo "$RHOST" | cut -d":" -f2)
+    RHOST=$(echo "$RHOST" | cut -d":" -f1)
+    RPORT_ARG="-p ${RPORT}"
+  else
+    # defaults
+    RPORT=""
+    RPORT_ARG=""
+  fi
+
   echo "[INFO] Trying ${RHOST}"
-  
-  STATUS=$(ssh -n -o StrictHostKeyChecking=no -o BatchMode=yes -o ConnectTimeout=5 ${SSH_KEY_ARG} ${RHOST} "echo -n"; echo $?)
+
+  STATUS=$(ssh -n -o StrictHostKeyChecking=no -o BatchMode=yes -o ConnectTimeout=5 ${RPORT_ARG} ${SSH_KEY_ARG} "${RHOST}" "echo -n"; echo $?)
 
   if [ $STATUS != 0 ]; then
     echo -n "[ERROR] No SSH login possible for ${RHOST}. "
@@ -50,12 +62,12 @@ while read line; do
       exit 1
     else
       echo "Adding public key with password: "
-      cat "${SSH_KEY}".pub | ssh ${RHOST} 'cat >> ~/.ssh/authorized_keys'
+      cat "${SSH_KEY}".pub | ssh -o StrictHostKeyChecking=no ${RPORT_ARG} ${SSH_KEY_ARG} "${RHOST}" 'cat >> ~/.ssh/authorized_keys'
     fi
   else
     echo "[SUCCESS] SSH login possible for ${RHOST}."
   fi
-  
+
   echo
 
 done < "$HOSTS"

uberspace-backup.sh

@@ -2,11 +2,11 @@
 #  SPDX-FileCopyrightText: 2019 Max Mehl <mail [at] mehl [dot] mx>
 #  SPDX-License-Identifier: GPL-3.0-or-later
 ########################################################################
-#  
-#  Saves specific files and directories from a remote server via SSH. 
+#
+#  Saves specific files and directories from a remote server via SSH.
 #  Provides easy shortcuts for Uberspace.de hosts.
 #  README.md provides more details.
-#  
+#
 ########################################################################
 
 # Set correct UTF-8 encoding (for FreeBSD jail)
@@ -18,7 +18,7 @@ source "$CURDIR"/config.cfg
 
 if [ ! -e "${HOSTS}" ]; then echo "Missing hosts file. Please set a correct value of HOSTS= in your config file. Current value: ${HOSTS}"; exit 1; fi
 
-if [ ! -z "${SSH_KEY}" ]; then
+if [ -n "${SSH_KEY}" ]; then
   SSH_KEY_ARG="-i ${SSH_KEY}"
 else
   # defaults
@@ -43,29 +43,41 @@ function logecho {
   echo "$(pdate) $@" >> "$LOG"
 }
 
-while read line; do
+while read -r line; do
   # if line is a comment or blank, go to next line
-  if $(echo "$line" | grep -qE "^\s*(#|$)"); then continue; fi
+  if echo "$line" | grep -qE "^\s*(#|$)"; then continue; fi
 
   RHOST=$(echo "$line" | cut -d";" -f1 | trim)
   RUSER=$(echo "$RHOST" | cut -d"@" -f1)
   ALLRDIR=$(echo "$line" | cut -d";" -f2 | trim)
   US_VERSION=$(echo "$line" | cut -d";" -f3 | trim)
-  
+
+  # Get SSH port if needed
+  if echo "$RHOST" | grep -q ":"; then
+    RPORT=$(echo "$RHOST" | cut -d":" -f2)
+    RHOST=$(echo "$RHOST" | cut -d":" -f1)
+    RPORT_ARG="-p ${RPORT}"
+  else
+    # defaults
+    RPORT=""
+    RPORT_ARG=""
+  fi
+
   logecho "${RHOST}: Starting backups"
 
+  # Task ssh-checker.sh to check this host
   if ! "${CURDIR}"/ssh-checker.sh "${RHOST}"; then
     logecho "${RHOST}: ERROR when connecting via SSH. Please run ssh-checker.sh to debug."
     logecho "${RHOST}: Aborting backup after an error."
     continue
   fi
-  
-  NORDIR=$(echo $ALLRDIR | grep -o "|" | wc -l)
-  NORDIR=$[$NORDIR + 1]
-    
+
+  NORDIR=$(echo "$ALLRDIR" | grep -o "|" | wc -l)
+  NORDIR=$(($NORDIR + 1))
+
   for ((i = 1; i <= $NORDIR; i++)); do
     RDIR=$(echo "$ALLRDIR" | cut -d"|" -f${i} | trim)
-    
+
     if [ "${RDIR}" == "%virtual" ]; then
       RDIR=/var/www/virtual/${RUSER}
       DEST="$BACKUPDIR/$RHOST/$DATE/virtual"
@@ -81,7 +93,7 @@ while read line; do
     else
       DEST="$BACKUPDIR/$RHOST/$DATE/$(basename "${RDIR}")"
     fi
-    
+
     # Set Source directory, and make exception for %mysql
     SOURCE="${RDIR}"
     if [ "${RDIR}" == "mysql" ]; then
@@ -91,28 +103,28 @@ while read line; do
         SOURCE=/mysql_backup/current/${RUSER}
       fi
     fi
-    
+
     # Create backup destination if necessary
     if [ ! -e "${DEST}" ]; then mkdir -p "${DEST}"; fi
-    
+
     # RSYNC
     logecho "${RHOST}: Downloading ${SOURCE} to ${DEST}"
-    rsync -a -e "ssh -q -o StrictHostKeyChecking=no -o UserKnownHostsFile=/dev/null -o Compression=no -T -x ${SSH_KEY_ARG}" ${RHOST}:${SOURCE}/ "${DEST}"/
-        
+    rsync -a -e "ssh -q -o StrictHostKeyChecking=no -o UserKnownHostsFile=/dev/null -o Compression=no -T -x ${RPORT_ARG} ${SSH_KEY_ARG}" "${RHOST}:${SOURCE}"/ "${DEST}"/
+
     # Pack backup directory, and delete uncompressed one
-    logecho "${RHOST}: Archiving $(basename ${DEST})"
-    tar cf ${DEST}.tar -C $(echo ${DEST} | sed "s|$(basename ${DEST})$||") $(basename ${DEST}) # TODO: avoid absolute paths
-    rm -rf ${DEST}
-    
+    logecho "${RHOST}: Archiving $(basename "${DEST}")"
+    tar cf "${DEST}".tar -C $(echo ${DEST} | sed "s|$(basename ${DEST})$||") $(basename ${DEST}) # TODO: avoid absolute paths
+    rm -rf "${DEST}"
+
     # Encrypt archive with GPG (it compresses at the same time)
-    logecho "${RHOST}: Encrypting and compressing $(basename ${DEST})"
-    gpg --output ${DEST}.tar.gpg --encrypt --recipient ${GPG} ${DEST}.tar
-    rm ${DEST}.tar
-    
+    logecho "${RHOST}: Encrypting and compressing $(basename "${DEST}")"
+    gpg --output "${DEST}".tar.gpg --encrypt --recipient ${GPG} "${DEST}".tar
+    rm "${DEST}".tar
+
     # Delete all old directories except the $MAXBAK most recent
     if [ $(ls -tp "${BACKUPDIR}"/"${RHOST}"/ | grep '/$' | wc -l | tr -d ' ') -gt $MAXBAK ]; then
-      logecho "${RHOST}: Removing older backups of $(basename ${DEST})"
-      ls -tpd "${BACKUPDIR}"/"${RHOST}"/* | grep '/$' | tail -n +$[$MAXBAK + 1] | xargs -0 | xargs rm -r --
+      logecho "${RHOST}: Removing older backups of $(basename "${DEST}")"
+      ls -tpd "${BACKUPDIR}"/"${RHOST}"/* | grep '/$' | tail -n +$(($MAXBAK + 1)) | xargs -0 | xargs rm -r --
     fi
   done