duckDNS_updater_v3.0RC2

#!/bin/sh
# Dependencies:
#  Required:
#   ifconfig && grep && wc && awk && ( curl || wget )
#  Recommended:
#   stat ca-certificates
# Notes:
#  Change eth0 to the correct interface, see ifconfig output for details, if you are behind a router and dont care to look it up "lo" should work

# Basic Configuration Options:
DOMAIN="YOUR_SUB-DOMAIN_HERE"
TOKEN="YOUR_TOKEN_HERE"
LOG="/tmp/duckdns"
NIC="eth0"
DEBUG="off"

# Advanced Configuration Options:
IP="$LOG.log"
TIME="$LOG-time.log"
WARN="$LOG-warn.log"
ERROR="$LOG-warn.log"

# NEW=$(hostname -I) # If this works (and gets the right address) use this, some systems may use -i

# You should not need to edit anything below this line

if [ -z "$NEW" ];then
    NEW=$(/sbin/ifconfig $NIC | awk -F':' '/inet addr/{split($2,_," ");print _[1]}')
fi
if [ $(echo $NEW | grep '^192.168.\|^10.\|^127.\|^172.1[6-9].\|^172.2[0-9].\|^172.3[0-1].\|^169.254.[1-2]' | wc -l) -eq 1 ];then
    # Match IP range:     192.168.   10.   127.      -->       172.(16-31).      <--        169.254.(1,2)
    echo "Using external IP check, use 11 second intervals or more to avoid being blocked" >> "$WARN"
    if [ $(type curl > /dev/null;echo $?) -eq 0 ];then
        NEW=$(curl http://ipecho.net/plain 2>/dev/null)
    else
        NEW=$(wget -qO- http://ipecho.net/plain)
    fi
    if [ $? -ne 0 ];then
        echo "Failed to get external IP" >> "$ERROR"
        exit
    fi
fi
TAT=1
if [ $(type stat > /dev/null;echo $?) -eq 0 ];then
    TAT=0;
fi
if [ -n "$NEW" ];then
    if [ -f "$IP" ];then
        if [ $TAT -eq 0 ];then
            THEN=$(stat -c "%Y" "$IP")
        else
            THEN=$(cat "$TIME")
        fi
        OLD=$(cat "$IP")
    else
        THEN=864000
        OLD="0.0.0.0"
    fi
    NOW=$(date +%s)
    if [ "$OLD" != "$NEW" ] || [ $(($NOW-$THEN)) -gt 863999 ];then
        S="https://"
        D="http://"
        URL="www.duckdns.org/update?domains=$DOMAIN&token=$TOKEN&ip=$NEW"
        if [ $DEBUG != "off" ];then
            echo $URL
        fi
        if [ $(type curl > /dev/null;echo $?) -eq 0 ];then
            NOW=$(curl "$S$URL" 2>/dev/null)
            if [ $? -eq 77 ];then
                echo "Looks like ca-certificates is missing or outdated" >> "$WARN"
                NOW=$(curl -k "$S$URL" 2>/dev/null)
            fi
        else
            NOW=$(wget -q -O - "$S$@" "$URL")
            if  [ $? -eq 1 ];then
                if [ $(wget --help|grep '--no-check-certificate') ];then
                    echo "Looks like ca-certificates is missing or outdated" >> "$WARN"
                    NOW=$(wget --no-check-certificate -q -O - "$@" "$S$URL")
                else
                    echo "wget does not appear to support SSL" >> "$WARN"
                    NOW=$(wget -q -O - "$@" "$D$URL")
                fi
            fi
        fi
        if [ "$NOW" = "OK" ]; then
            echo "$NEW" > "$IP"
            if [ $TAT -eq 1 ];then
                echo "$(date +%s)" > "$TIME"
            fi
        elif [ "$NOW" = "KO" ]; then
            echo "Double-check your Token/Domain" >> "$ERROR"
        else
            echo "$NOW" >> "$ERROR"
        fi
    fi
fi
if [ $DEBUG != "off" ];then
    if [ -f "$ERROR" ];then
        ls -l "$ERROR"
        echo "Error Log:"
        cat "$ERROR"
        echo '--------------------'
    fi
    if [ -f "$WARN" ];then
        ls -l "$WARN"
        echo "Warning Log:"
        cat "$WARN"
        echo '--------------------'
    fi
    if [ -f "$IP" ];then
        ls -l "$IP"
        echo "Last IP:"
        cat "$IP"
    else
        echo "NO last IP, well this is not good"
    fi
else
    if [ $(cat "$ERROR" | wc -l) -gt 16 ];then
        cat "$ERROR" | tail -8 > "$ERROR"
    fi
    if [ $(cat "$WARN" | wc -l) -gt 16 ];then
        cat "$WARN" | tail -8 > "$WARN"
    fi
fi