436 lines
18 KiB
Bash
436 lines
18 KiB
Bash
#!/bin/sh
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# /usr/lib/ddns/dynamic_dns_updater.sh
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#
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#.Distributed under the terms of the GNU General Public License (GPL) version 2.0
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# Original written by Eric Paul Bishop, January 2008
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# (Loosely) based on the script on the one posted by exobyte in the forums here:
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# http://forum.openwrt.org/viewtopic.php?id=14040
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# extended and partial rewritten
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#.2014-2018 Christian Schoenebeck <christian dot schoenebeck at gmail dot com>
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#
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# variables in small chars are read from /etc/config/ddns
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# variables in big chars are defined inside these scripts as global vars
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# variables in big chars beginning with "__" are local defined inside functions only
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# set -vx #script debugger
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. $(dirname $0)/dynamic_dns_functions.sh # global vars are also defined here
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usage() {
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cat << EOF
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Usage:
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$MYPROG [options] -- command
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Commands:
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start Start SECTION or NETWORK or all
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stop Stop NETWORK or all
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Parameters:
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-n NETWORK Start/Stop sections in background monitoring NETWORK, force VERBOSE=0
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-S SECTION SECTION to start
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use either -N NETWORK or -S SECTION
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-h show this help and exit
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-V show version and exit
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-v LEVEL VERBOSE=LEVEL (default 1)
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'0' NO output to console
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'1' output to console
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'2' output to console AND logfile
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+ run once WITHOUT retry on error
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-d dry run (don't send any changes)
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EOF
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}
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usage_err() {
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printf %s\\n "$MYPROG: $@" >&2
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usage >&2
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exit 1
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}
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while getopts ":hv:dn:S:V" OPT; do
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case "$OPT" in
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h) usage; exit 0;;
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v) VERBOSE=$OPTARG;;
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d) DRY_RUN=1;;
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n) NETWORK=$OPTARG;;
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S) SECTION_ID=$OPTARG;;
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V) printf %s\\n "ddns-scripts $VERSION"; exit 0;;
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:) usage_err "option -$OPTARG missing argument";;
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\?) usage_err "invalid option -$OPTARG";;
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*) usage_err "unhandled option -$OPT $OPTARG";;
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esac
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done
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shift $((OPTIND - 1 )) # OPTIND is 1 based
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[ -n "$NETWORK" -a -n "$SECTION_ID" ] && usage_err "use either option '-N' or '-S' not both"
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[ $# -eq 0 ] && usage_err "missing command"
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[ $# -gt 1 ] && usage_err "to much commands"
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case "$1" in
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start)
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if [ -n "$NETWORK" ]; then
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start_daemon_for_all_ddns_sections "$NETWORK"
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exit 0
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fi
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if [ -z "$SECTION_ID" ]; then
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start_daemon_for_all_ddns_sections
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exit 0
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fi
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;;
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stop)
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if [ -n "$INTERFACE" ]; then
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stop_daemon_for_all_ddns_sections "$NETWORK"
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exit 0
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else
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stop_daemon_for_all_ddns_sections
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exit 0
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fi
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exit 1
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;;
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reload)
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killall dynamic_dns_updater.sh 2>/dev/null
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exit $?
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;;
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*) usage_err "unknown command - $1";;
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esac
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# set file names
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PIDFILE="$ddns_rundir/$SECTION_ID.pid" # Process ID file
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UPDFILE="$ddns_rundir/$SECTION_ID.update" # last update successful send (system uptime)
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DATFILE="$ddns_rundir/$SECTION_ID.dat" # save stdout data of WGet and other extern programs called
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ERRFILE="$ddns_rundir/$SECTION_ID.err" # save stderr output of WGet and other extern programs called
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IPFILE="$ddns_rundir/$SECTION_ID.ip" #
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LOGFILE="$ddns_logdir/$SECTION_ID.log" # log file
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# VERBOSE > 1 delete logfile if exist to create an empty one
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# only with this data of this run for easier diagnostic
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# new one created by write_log function
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[ $VERBOSE -gt 1 -a -f $LOGFILE ] && rm -f $LOGFILE
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# Previously -v 3 could we used for dry run
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[ $VERBOSE -ge 3 ] && DRY_RUN=1
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# TRAP handler
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trap "trap_handler 0 \$?" 0 # handle script exit with exit status
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trap "trap_handler 1" 1 # SIGHUP Hangup / reload config
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trap "trap_handler 2" 2 # SIGINT Terminal interrupt
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trap "trap_handler 3" 3 # SIGQUIT Terminal quit
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# trap "trap_handler 9" 9 # SIGKILL no chance to trap
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trap "trap_handler 15" 15 # SIGTERM Termination
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################################################################################
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# Leave this comment here, to clearly document variable names that are expected/possible
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# Use load_all_config_options to load config options, which is a much more flexible solution.
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#
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# config_load "ddns"
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# config_get <variable> $SECTION_ID <option>
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#
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# defined options (also used as variable):
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#
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# enabled self-explanatory
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# interface network interface used by hotplug.d i.e. 'wan' or 'wan6'
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#
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# service_name Which DDNS service do you use or "custom"
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# update_url URL to use to update your "custom" DDNS service
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# update_script SCRIPT to use to update your "custom" DDNS service
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#
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# lookup_host FQDN of ONE of your at DDNS service defined host / required to validate if IP update happen/necessary
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# domain Nomally your DDNS hostname / replace [DOMAIN] in update_url
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# username Username of your DDNS service account / urlenceded and replace [USERNAME] in update_url
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# password Password of your DDNS service account / urlencoded and replace [PASSWORD] in update_url
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# param_enc Optional parameter for (later) usage / urlencoded and replace [PARAMENC] in update_url
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# param_opt Optional parameter for (later) usage / replace [PARAMOPT] in update_url
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#
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# use_https use HTTPS to update DDNS service
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# cacert file or directory where HTTPS can find certificates to verify server; 'IGNORE' ignore check of server certificate
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#
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# use_syslog log activity to syslog
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#
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# ip_source source to detect current IP ('network' or 'web' or 'script' or 'interface')
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# ip_network local defined network to read IP from i.e. 'wan' or 'wan6'
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# ip_url URL to read current IP from i.e. http://checkip.dyndns.com/ or http://checkipv6.dyndns.com/
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# ip_script full path and name of your script to detect current IP
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# ip_interface physical interface to use for detecting
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#
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# check_interval check for changes every !!! checks below 10 minutes make no sense because the Internet
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# check_unit 'days' 'hours' 'minutes' !!! needs about 5-10 minutes to sync an IP-change for an DNS entry
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#
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# force_interval force to send an update to your service if no change was detected
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# force_unit 'days' 'hours' 'minutes' !!! force_interval="0" runs this script once for use i.e. with cron
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#
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# retry_interval if error was detected retry in
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# retry_unit 'days' 'hours' 'minutes' 'seconds'
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# retry_max_count number of retries before scripts stops
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#
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# use_ipv6 detecting/sending IPv6 address
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# force_ipversion force usage of IPv4 or IPv6 for the whole detection and update communication
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# dns_server using a non default dns server to get Registered IP from Internet
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# force_dnstcp force communication with DNS server via TCP instead of default UDP
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# proxy using a proxy for communication !!! ALSO used to detect current IP via web => return proxy's IP !!!
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# use_logfile self-explanatory "/var/log/ddns/$SECTION_ID.log"
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# is_glue the record that should be updated is a glue record
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#
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# some functionality needs
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# - GNU Wget or cURL installed for sending updates to DDNS service
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# - BIND host installed to detect Registered IP
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#
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################################################################################
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load_all_config_options "ddns" "$SECTION_ID"
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ERR_LAST=$? # save return code - equal 0 if SECTION_ID found
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# set defaults if not defined
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[ -z "$enabled" ] && enabled=0
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[ -z "$retry_max_count" ] && retry_max_count=0 # endless retry
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[ -z "$use_syslog" ] && use_syslog=2 # syslog "Notice"
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[ -z "$use_https" ] && use_https=0 # not use https
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[ -z "$use_logfile" ] && use_logfile=1 # use logfile by default
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[ -z "$use_ipv6" ] && use_ipv6=0 # use IPv4 by default
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[ -z "$force_ipversion" ] && force_ipversion=0 # default let system decide
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[ -z "$force_dnstcp" ] && force_dnstcp=0 # default UDP
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[ -z "$ip_source" ] && ip_source="network"
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[ -z "$is_glue" ] && is_glue=0 # default the ddns record is not a glue record
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[ "$ip_source" = "network" -a -z "$ip_network" -a $use_ipv6 -eq 0 ] && ip_network="wan" # IPv4: default wan
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[ "$ip_source" = "network" -a -z "$ip_network" -a $use_ipv6 -eq 1 ] && ip_network="wan6" # IPv6: default wan6
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[ "$ip_source" = "web" -a -z "$ip_url" -a $use_ipv6 -eq 0 ] && ip_url="http://checkip.dyndns.com"
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[ "$ip_source" = "web" -a -z "$ip_url" -a $use_ipv6 -eq 1 ] && ip_url="http://checkipv6.dyndns.com"
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[ "$ip_source" = "interface" -a -z "$ip_interface" ] && ip_interface="eth1"
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# url encode username (might be email or something like this)
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# and password (might have special chars for security reason)
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# and optional parameter "param_enc"
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[ -n "$username" ] && urlencode URL_USER "$username"
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[ -n "$password" ] && urlencode URL_PASS "$password"
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[ -n "$param_enc" ] && urlencode URL_PENC "$param_enc"
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# SECTION_ID does not exists
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[ $ERR_LAST -ne 0 ] && {
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[ $VERBOSE -le 1 ] && VERBOSE=2 # force console out and logfile output
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[ -f $LOGFILE ] && rm -f $LOGFILE # clear logfile before first entry
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write_log 7 "************ ************** ************** **************"
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write_log 5 "PID '$$' started at $(eval $DATE_PROG)"
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write_log 7 "ddns version : $VERSION"
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write_log 7 "uci configuration:${N}$(uci -q show ddns | grep '=service' | sort)"
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write_log 14 "Service section '$SECTION_ID' not defined"
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}
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write_log 7 "************ ************** ************** **************"
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write_log 5 "PID '$$' started at $(eval $DATE_PROG)"
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write_log 7 "ddns version : $VERSION"
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write_log 7 "uci configuration:${N}$(uci -q show ddns.$SECTION_ID | sort)"
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# write_log 7 "ddns version : $(opkg list-installed ddns-scripts | cut -d ' ' -f 3)"
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case $VERBOSE in
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0) write_log 7 "verbose mode : 0 - run normal, NO console output";;
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1) write_log 7 "verbose mode : 1 - run normal, console mode";;
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2) write_log 7 "verbose mode : 2 - run once, NO retry on error";;
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*) write_log 14 "error detecting VERBOSE '$VERBOSE'";;
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esac
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[ $DRY_RUN -ge 1 ] && write_log 7 "Dry Run: NOT sending update"
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# check enabled state otherwise we don't need to continue
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[ $enabled -eq 0 ] && write_log 14 "Service section disabled!"
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# determine what update url we're using if a service_name is supplied
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# otherwise update_url is set inside configuration (custom update url)
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# or update_script is set inside configuration (custom update script)
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[ -n "$service_name" ] && {
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# Check first if we have a custom service provider with this name
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get_service_data "$service_name" "/usr/share/ddns/custom" update_url update_script UPD_ANSWER
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if [ "$?" != "0" ]; then
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get_service_data "$service_name" "/usr/share/ddns/default" update_url update_script UPD_ANSWER
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fi
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}
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[ -z "$update_url" -a -z "$update_script" ] && write_log 14 "No update_url found/defined or no update_script found/defined!"
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[ -n "$update_script" -a ! -f "$update_script" ] && write_log 14 "Custom update_script not found!"
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# temporary needed to convert existing uci settings
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[ -z "$lookup_host" ] && {
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uci -q set ddns.$SECTION_ID.lookup_host="$domain"
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uci -q commit ddns
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lookup_host="$domain"
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}
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# later versions only check if configured correctly
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# without lookup host and possibly other required options we can do nothing for you
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[ -z "$lookup_host" ] && write_log 14 "Service section not configured correctly! Missing 'lookup_host'"
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# verify validity of variables
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[ -n "$lookup_host" ] && sanitize_variable lookup_host "$DNS_CHARSET" ""
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[ -n "$dns_server" ] && sanitize_variable dns_server "$DNS_CHARSET" ""
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[ -n "$domain" ] && sanitize_variable domain "$DNS_CHARSET_DOMAIN" ""
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# Filter shell escape characters, if these are required in the URL, they
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# can still be passed url encoded
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[ -n "$param_opt" ] && sanitize_variable param_opt "" "$SHELL_ESCAPE"
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[ -n "$update_url" ] && {
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# only check if update_url is given, update_scripts have to check themselves
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[ -z "$domain" ] && $(echo "$update_url" | grep "\[DOMAIN\]" >/dev/null 2>&1) && \
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write_log 14 "Service section not configured correctly! Missing 'domain'"
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[ -z "$username" ] && $(echo "$update_url" | grep "\[USERNAME\]" >/dev/null 2>&1) && \
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write_log 14 "Service section not configured correctly! Missing 'username'"
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[ -z "$password" ] && $(echo "$update_url" | grep "\[PASSWORD\]" >/dev/null 2>&1) && \
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write_log 14 "Service section not configured correctly! Missing 'password'"
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[ -z "$param_enc" ] && $(echo "$update_url" | grep "\[PARAMENC\]" >/dev/null 2>&1) && \
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write_log 14 "Service section not configured correctly! Missing 'param_enc'"
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[ -z "$param_opt" ] && $(echo "$update_url" | grep "\[PARAMOPT\]" >/dev/null 2>&1) && \
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write_log 14 "Service section not configured correctly! Missing 'param_opt'"
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}
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# verify ip_source 'script' if script is configured and executable
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if [ "$ip_source" = "script" ]; then
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set -- $ip_script #handling script with parameters, we need a trick
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[ -z "$1" ] && write_log 14 "No script defined to detect current IP!"
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[ -x "$1" ] || write_log 14 "Script to detect current IP not executable!"
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fi
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# compute update interval in seconds
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get_seconds CHECK_SECONDS ${check_interval:-10} ${check_unit:-"minutes"} # default 10 min
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get_seconds FORCE_SECONDS ${force_interval:-72} ${force_unit:-"hours"} # default 3 days
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get_seconds RETRY_SECONDS ${retry_interval:-60} ${retry_unit:-"seconds"} # default 60 sec
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[ $CHECK_SECONDS -lt 300 ] && CHECK_SECONDS=300 # minimum 5 minutes
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[ $FORCE_SECONDS -gt 0 -a $FORCE_SECONDS -lt $CHECK_SECONDS ] && FORCE_SECONDS=$CHECK_SECONDS # FORCE_SECONDS >= CHECK_SECONDS or 0
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write_log 7 "check interval: $CHECK_SECONDS seconds"
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write_log 7 "force interval: $FORCE_SECONDS seconds"
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write_log 7 "retry interval: $RETRY_SECONDS seconds"
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write_log 7 "retry max count : $retry_max_count times"
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# kill old process if it exists & set new pid file
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stop_section_processes "$SECTION_ID"
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[ $? -gt 0 ] && write_log 7 "'SIGTERM' was send to old process" || write_log 7 "No old process"
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echo $$ > $PIDFILE
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# determine when the last update was
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# the following lines should prevent multiple updates if hotplug fires multiple startups
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# as described in Ticket #7820, but did not function if never an update take place
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# i.e. after a reboot (/var is linked to /tmp)
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# using uptime as reference because date might not be updated via NTP client
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get_uptime CURR_TIME
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[ -e "$UPDFILE" ] && {
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LAST_TIME=$(cat $UPDFILE)
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# check also LAST > CURR because link of /var/run to /tmp might be removed
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# i.e. boxes with larger filesystems
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[ -z "$LAST_TIME" ] && LAST_TIME=0
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[ $LAST_TIME -gt $CURR_TIME ] && LAST_TIME=0
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}
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if [ $LAST_TIME -eq 0 ]; then
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write_log 7 "last update: never"
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else
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EPOCH_TIME=$(( $(date +%s) - $CURR_TIME + $LAST_TIME ))
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EPOCH_TIME="date -d @$EPOCH_TIME +'$ddns_dateformat'"
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write_log 7 "last update: $(eval $EPOCH_TIME)"
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fi
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# verify DNS server
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[ -n "$dns_server" ] && verify_dns "$dns_server"
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# verify Proxy server and set environment
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[ -n "$proxy" ] && {
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verify_proxy "$proxy" && {
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# everything ok set proxy
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export HTTP_PROXY="http://$proxy"
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export HTTPS_PROXY="http://$proxy"
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export http_proxy="http://$proxy"
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export https_proxy="http://$proxy"
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}
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}
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# let's check if there is already an IP registered on the web
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get_registered_ip REGISTERED_IP "NO_RETRY"
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ERR_LAST=$?
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# No error or No IP set otherwise retry
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[ $ERR_LAST -eq 0 -o $ERR_LAST -eq 127 ] || get_registered_ip REGISTERED_IP
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# on IPv6 we use expanded version to be shure when comparing
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[ $use_ipv6 -eq 1 ] && expand_ipv6 "$REGISTERED_IP" REGISTERED_IP
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# loop endlessly, checking ip every check_interval and forcing an updating once every force_interval
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write_log 6 "Starting main loop at $(eval $DATE_PROG)"
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while : ; do
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get_current_ip CURRENT_IP # read current IP
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[ $use_ipv6 -eq 1 ] && expand_ipv6 "$CURRENT_IP" CURRENT_IP # on IPv6 we use expanded version
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# prepare update
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# never updated or forced immediate then NEXT_TIME = 0
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[ $FORCE_SECONDS -eq 0 -o $LAST_TIME -eq 0 ] \
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&& NEXT_TIME=0 \
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|| NEXT_TIME=$(( $LAST_TIME + $FORCE_SECONDS ))
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get_uptime CURR_TIME # get current uptime
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# send update when current time > next time or current ip different from registered ip
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if [ $CURR_TIME -ge $NEXT_TIME -o "$CURRENT_IP" != "$REGISTERED_IP" ]; then
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if [ $DRY_RUN -ge 1 ]; then
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write_log 7 "Dry Run: NO UPDATE send"
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elif [ "$CURRENT_IP" != "$REGISTERED_IP" ]; then
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write_log 7 "Update needed - L: '$CURRENT_IP' <> R: '$REGISTERED_IP'"
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else
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write_log 7 "Forced Update - L: '$CURRENT_IP' == R: '$REGISTERED_IP'"
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fi
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ERR_LAST=0
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[ $DRY_RUN -eq 0 ] && {
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send_update "$CURRENT_IP"
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ERR_LAST=$? # save return value
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}
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# error sending current IP to provider
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# we have no communication error (handled inside send_update/do_transfer)
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# but update was not recognized
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# do NOT retry after RETRY_SECONDS, do retry after CHECK_SECONDS
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# to early retrys will block most DDNS provider
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# providers answer is checked inside send_update() function
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if [ $ERR_LAST -eq 0 ]; then
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get_uptime LAST_TIME # we send update, so
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echo $LAST_TIME > $UPDFILE # save LASTTIME to file
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[ "$CURRENT_IP" != "$REGISTERED_IP" ] \
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&& write_log 6 "Update successful - IP '$CURRENT_IP' send" \
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|| write_log 6 "Forced update successful - IP: '$CURRENT_IP' send"
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elif [ $ERR_LAST -eq 127 ]; then
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write_log 3 "No update send to DDNS Provider"
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else
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write_log 3 "IP update not accepted by DDNS Provider"
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fi
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fi
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# now we wait for check interval before testing if update was recognized
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[ $DRY_RUN -eq 0 ] && {
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write_log 7 "Waiting $CHECK_SECONDS seconds (Check Interval)"
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sleep $CHECK_SECONDS &
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PID_SLEEP=$!
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wait $PID_SLEEP # enable trap-handler
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PID_SLEEP=0
|
|
} || write_log 7 "Dry Run: NO Check Interval waiting"
|
|
|
|
REGISTERED_IP="" # clear variable
|
|
get_registered_ip REGISTERED_IP # get registered/public IP
|
|
[ $use_ipv6 -eq 1 ] && expand_ipv6 "$REGISTERED_IP" REGISTERED_IP # on IPv6 we use expanded version
|
|
|
|
# IP's are still different
|
|
if [ "$CURRENT_IP" != "$REGISTERED_IP" ]; then
|
|
if [ $VERBOSE -le 1 ]; then # VERBOSE <=1 then retry
|
|
RETRY_COUNT=$(( $RETRY_COUNT + 1 ))
|
|
[ $retry_max_count -gt 0 -a $RETRY_COUNT -gt $retry_max_count ] && \
|
|
write_log 14 "Updating IP at DDNS provider failed after $retry_max_count retries"
|
|
write_log 4 "Updating IP at DDNS provider failed - starting retry $RETRY_COUNT/$retry_max_count"
|
|
continue # loop to beginning
|
|
else
|
|
write_log 4 "Updating IP at DDNS provider failed"
|
|
write_log 7 "Verbose Mode: $VERBOSE - NO retry"; exit 1
|
|
fi
|
|
else
|
|
# we checked successful the last update
|
|
RETRY_COUNT=0 # reset error counter
|
|
fi
|
|
|
|
# force_update=0 or VERBOSE > 1 - leave here
|
|
[ $VERBOSE -gt 1 ] && write_log 7 "Verbose Mode: $VERBOSE - NO reloop"
|
|
[ $FORCE_SECONDS -eq 0 ] && write_log 6 "Configured to run once"
|
|
[ $VERBOSE -gt 1 -o $FORCE_SECONDS -eq 0 ] && exit 0
|
|
|
|
write_log 6 "Rerun IP check at $(eval $DATE_PROG)"
|
|
done
|
|
# we should never come here there must be a programming error
|
|
write_log 12 "Error in 'dynamic_dns_updater.sh - program coding error"
|