backupninja/handlers/borg.helper.in

# -*- mode: sh; sh-basic-offset: 3; indent-tabs-mode: nil; -*-
# vim: set filetype=sh sw=3 sts=3 expandtab autoindent:
#
# Copyright 2016 Benjamin Maisonnas <ben@wainei.net>
#
# This work is free. You can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#

HELPERS="$HELPERS borg:deduplicated_archive_based_backup"

declare -a borg_includes
declare -a borg_excludes

# FUNCTIONS

do_borg_host_includes() {
   set -o noglob
   # choose the files to backup
   REPLY=
   while [ -z "$REPLY" ]; do
      formBegin "$borg_title - host system: includes"
         for ((i=0; i < ${#borg_includes[@]} ; i++)); do
            formItem include ${borg_includes[$i]}
         done
         formItem include
         formItem include
         formItem include
         formItem include
         formItem include
         formItem include
         formItem include
         formItem include
      formDisplay
      [ $? = 0 ] || return
      unset borg_includes
      borg_includes=($REPLY)
   done
   set +o noglob
}

do_borg_excludes() {
   set -o noglob
   formBegin "$borg_title: host system: excludes"
     for ((i=0; i < ${#borg_excludes[@]} ; i++))
     do
       formItem exclude ${borg_excludes[$i]}
     done
     formItem exclude
     formItem exclude
     formItem exclude
     formItem exclude
     formItem exclude
     formItem exclude
     formItem exclude
     formItem exclude
   formDisplay
   [ $? = 0 ] || return
   unset borg_excludes
   borg_excludes=($REPLY)
   set +o noglob
}

do_borg_src() {
   do_borg_host_includes
   [ $? = 0 ] || return 1

   do_borg_excludes
   [ $? = 0 ] || return 1

   _src_done="(DONE)"
   setDefault dest
}

do_borg_dest() {
   declare -a tmp_array

   set -o noglob
   REPLY=
   while [ -z "$REPLY" -o -z "$borg_directory" -o -z "$borg_host" -o -z "$borg_user" -o -z "$borg_archive" -o -z "$borg_compression" ]
   do
     formBegin "$borg_title - destination"
        formItem "directory" "$borg_directory"
        formItem "host" "$borg_host"
        formItem "user" "$borg_user"
        formItem "archive_name" "$borg_archive"
        formItem "compression" "$borg_compression"

        formDisplay
     [ $? = 0 ] || return
     tmp_array=($REPLY)
     borg_directory=${tmp_array[0]}
     borg_host=${tmp_array[1]}
     borg_user=${tmp_array[2]}
     borg_archive=${tmp_array[3]}
     borg_compression=${tmp_array[4]}
  done
  set +o noglob

  _dest_done="(DONE)"
  setDefault conn
}

do_borg_enc() {
   radioBox "$borg_title" "Encryption mode" \
       "none"     "no encryption and no authentication" on \
       "repokey"  "encryption with a passphrase" off
   [ $? = 1 ] && return;
   borg_encryption="$REPLY"

   if [ "$borg_encryption" = "repokey" ]; then
      local question="Enter the passphrase needed to encrypt/decrypt the repository:"
      REPLY=
      while [ -z "$REPLY" -o -z "$borg_passphrase" ]; do
         passwordBox "$borg_title - " "$question"
         [ $? = 0 ] || return 1
         borg_passphrase="$REPLY"
      done
   fi

  _enc_done="(DONE)"
}

do_borg_local_dir() {
   local dir_status="ok"

   IFS=$' \t\n'
   if [ "$_dest_done" = "" ]; then
      msgBox "$borg_title: error" "You must first configure the destination."
      return 1
   fi

   echo "Testing to see if the borg backup directory exists and is writable"
   if [ test -d "$borg_directory" ]; then
      if [ test -w "$borg_directory" ]; then
         msgBox "destination directory is not writable!" "The destination directory is not writable by the user you specified. Please fix the permissions on the directory and then try again."
         dir_status=failed
      fi
   else
      booleanBox "Destination does not exist" "The destination backup directory does not exist, do you want me to create it for you?"
      if [ $? = 0 ]; then
         if mkdir -p "$borg_directory"; then
            msgBox "$borg_title: success" "Creation of the destination directory was a success!"
         else
            msgBox "$borg_title: error" "Creation of the destination directory failed, check the directory permissions."
            dir_status=failed
         fi
      fi
   fi

   [ "$dir_status" = "ok" ] || return 1
}

do_borg_ssh_con() {
   local remote_status="ok"

   IFS=$' \t\n'
   if [ "$_dest_done" = "" ]; then
      msgBox "$borg_title: error" "You must first configure the destination."
      return 1
   elif [ "$borg_user" = "" ]; then
      msgBox "$borg_title: error" "You must first configure the destination user."
      return 1
   elif [ "$borg_host" = "" ]; then
      msgBox "$borg_title: error" "You must first configure the destination host."
      return 1
   else
      booleanBox "$borg_title" "This step will create a ssh key for the local root user with no passphrase (if one does not already exist), and attempt to copy root's public ssh key to authorized_keys file of $borg_user@$borg_host. This will allow the local root to make unattended backups to $borg_user@$borg_host.\n\n\nAre you sure you want to continue?"
      [ $? = 0 ] || return 1
   fi

   if [ ! -f /root/.ssh/id_dsa.pub -a ! -f /root/.ssh/id_rsa.pub ]; then
      echo "Creating local root's ssh key"
      ssh-keygen -t rsa -b 4096 -f /root/.ssh/id_rsa -N ""
      echo "Done. hit return to continue"
      read
   fi

   ssh -o PreferredAuthentications=publickey $borg_host -l $borg_user "exit" 2> /dev/null
   if [ $? -ne 0 ]; then
      echo "Copying root's public ssh key to authorized_keys of $borg_user@$borg_host. When prompted, specify the password for user $borg_user@$borg_host."
      pubkeys=( /root/.ssh/id_[rd]sa.pub )
      if ! ssh-copy-id -i ${pubkeys[0]} $borg_user@$borg_host; then
         echo "FAILED: Couldn't copy root's public ssh key to authorized_keys of $borg_user@$borg_host."
         ssh $borg_user@$borg_host 'test -w .ssh || test -w .'
         result=$?
         echo "Hit return to continue."
         read
         case $result in
            0 )   msgBox "$borg_title: error" "Directories are writable: Probably just a typo the first time." ;;
            1 )   msgBox "$borg_title: error" "Connected successfully to $borg_user@$borg_host, but unable to write. Check ownership and modes of ~$borg_user on $borg_host." ;;
            255 ) msgBox "$borg_title: error" "Failed to connect to $borg_user@$borg_host. Check hostname, username, and password. Also, make sure sshd is running on the destination host." ;;
            * )   msgBox "$borg_title: error" "Unexpected error (return code ${result})." ;;
         esac
         return
      else
         echo "Done. hit return to continue"
         read
      fi
   else
      echo "root@localhost is already in authorized_keys of $borg_user@$borg_host."
      echo "Hit return to continue."
      read
   fi

   # test to see if the remote borg backup directory exists and is writable
   echo "Testing to see if remote borg backup directory exists and is writable"
   ssh $borg_user@$borg_host "test -d ${borg_directory}"
   if [ $? = 0 ]; then
      ssh $borg_user@$borg_host "test -w $borg_directory"
      if [ $? != 0 ]; then
         msgBox "destination directory is not writable!" "The remote destination directory is not writable by the user you specified. Please fix the permissions on the directory and then try again."
         remote_status=failed
      fi
   else
      booleanBox "Remote directory does not exist" "The destination backup directory does not exist, do you want me to create it for you?"
      if [ $? = 0 ]; then
         ssh $borg_user@$borg_host "mkdir -p ${borg_directory}"
         result=$?
         case $result in
            0) msgBox "$borg_title: success" "Creation of the remote destination directory was a success!";;
            1) msgBox "$borg_title: error" "Connected successfully to $borg_user@$borg_host, but was unable to create the destination directory, check the directory permissions."
               remote_status=failed;;
            255) msgBox "$borg_title: error" "Failed to connect to $borg_user@$borg_host. Check hostname, username, and password. Also, make sure sshd is running on the destination host."
               remote_status=failed;;
            *) msgBox "$borg_title: error" "Unexpected error."
               remote_status=failed;;
         esac
      fi
   fi

   [ "$remote_status" = "ok" ] || return 1
}

do_borg_con() {
   echo "Checking for local install of borg"
   which borg
   if [ $? != 0 ]; then
      msgBox "$borg_title: error" "borg executable not found, please install borg ($borg_docs/installation.html)."
      return
   fi

   if [ "$borg_host" != "localhost" ]; then
      do_borg_ssh_con
   else
      do_borg_local_dir
   fi

   [ $? = 0 ] || return

   echo "SUCCESS: Everything looks good!"
   echo "Hit return to continue."
   read

   _con_done="(DONE)"
   setDefault finish
}

do_borg_prune() {
   radioBox "$borg_title" "pruning (how many backups to keep" \
       "yes" "regularly prune old backups" on \
       "no"  "keep all backups" off
   [ $? = 1 ] && return;
   borg_prune="$REPLY"

   if [ "$borg_prune" = "yes" ]; then
      declare -a tmp_array
      set -o noglob
      REPLY=
      formBegin "$borg_title - pruning (how many backups to keep)"
         formItem "hourly" "$borg_keephourly"
         formItem "daily" "$borg_keepdaily"
         formItem "weekly" "$borg_keepweekly"
         formItem "monthly" "$borg_keepmonthly"
         formDisplay

      [ $? = 0 ] || return
      tmp_array=($REPLY)
      borg_keephourly=${tmp_array[0]}
      borg_keepdaily=${tmp_array[1]}
      borg_keepweekly=${tmp_array[2]}
      borg_keepmonthly=${tmp_array[3]}

      set +o noglob
   fi

  _prune_done="(DONE)"
}

do_borg_finish() {
   get_next_filename $configdirectory/90.borg
   cat > $next_filename <<EOF
## for more options see
## - example.borg
## - $borg_docs

[source]
EOF
   ## includes ##
   set -o noglob
   for ((i=0; i < ${#borg_includes[@]} ; i++)); do
      echo "include = ${borg_includes[$i]}" >> $next_filename
   done
   set +o noglob

   ## excludes ##
   set -o noglob
   for ((i=0; i < ${#borg_excludes[@]} ; i++)); do
     echo exclude = ${borg_excludes[$i]} >> $next_filename
   done
   set +o noglob
   cat >> $next_filename <<EOF

## for more info see : borg prune -h
prune = $borg_prune
keephourly = $borg_keephourly
keepdaily = $borg_keepdaily
keepweekly = $borg_keepweekly
keepmonthly = $borg_keepmonthly

[dest]
directory = $borg_directory
host = $borg_host
user = $borg_user
archive = $borg_archive
compression = $borg_compression
encryption = $borg_encryption
passphrase = $borg_passphrase
EOF

   chmod 600 $next_filename
}

borg_main_menu() {
   while true; do
      srcitem="choose files to include & exclude $_src_done"
      destitem="configure backup destination $_dest_done"
      encitem="configure encryption mode $_enc_done"
      conitem="test connection and destination dir $_con_done"
      pruneitem="configure pruning (optional) $_prune_done"
      menuBox "$borg_title" "choose a step:" \
         src "$srcitem" \
         dest "$destitem" \
         enc "$encitem" \
         conn "$conitem" \
         prune "$pruneitem" \
         finish "finish and create config file"
      [ $? = 0 ] || return
      result="$REPLY"
      case "$result" in
         "src") do_borg_src;;
         "dest") do_borg_dest;;
         "enc") do_borg_enc;;
         "conn") do_borg_con;;
         "prune") do_borg_prune;;
         "finish")
            if [[ "$_con_done$_dest_done$_enc_done$_src_done" != "(DONE)(DONE)(DONE)(DONE)" ]]; then
               msgBox "$borg_title" "You cannot create the configuration file until mandatory steps are completed."
            else
               do_borg_finish
               return
            fi
            ;;
      esac
   done
}

borg_wizard() {
   # Global variables
   borg_title="borg action wizard"
   borg_docs="http://borgbackup.readthedocs.io/en/stable"

   _src_done=
   _dest_done=
   _enc_done=
   _con_done=

   borg_directory=/backup/`hostname`
   borg_user=root
   borg_host=localhost
   borg_archive='{now:%Y-%m-%dT%H:%M:%S}'
   borg_compression=lz4
   borg_encryption=none
   borg_passphrase=
   borg_keephourly=1
   borg_keepdaily=7
   borg_keepweekly=4
   borg_keepmonthly=-1

   # Global variables whose '*' shall not be expanded
   set -o noglob
   borg_includes=(/var/spool/cron/crontabs /var/backups /etc /root /home /usr/local/*bin)
   borg_excludes=(/home/*/.gnupg /home/*/.local/share/Trash /home/*/.Trash /home/*/.thumbnails)
   set +o noglob

   borg_main_menu
}