Add IPv6 + AAAA record support (Fixes orazioedoardo#3)

duckdns

@@ -3,6 +3,7 @@
 LANG=en_US.UTF-8
 
 LAST_IP="$HOME/.duckdns/last-ip"
+LAST_IPV6="$HOME/.duckdns/last-ipv6"
 CONFIG="$HOME/.duckdns/config"
 
 if [ -f "$CONFIG" ]; then
@@ -17,11 +18,22 @@ if [ ! -f "$LAST_IP" ]; then
         echo "$NEW_IP" > "$LAST_IP"
         logger -t duckdns "Initialization succeeded, domain: $DOMAIN.duckdns.org, IP: $NEW_IP"
     else
-        logger -t duckdns "Unable to detect the public IP address"
+        logger -t duckdns "Unable to detect the public IPv4 address"
         exit 1
     fi
 fi
 
+if [ ! -f "$LAST_IPV6" ]; then
+    if NEW_IPV6="$(dig +short -6 myip.opendns.com aaaa @resolver1.ipv6-sandbox.opendns.com)"; then
+        echo "$NEW_IPV6" > "$LAST_IPV6"
+        logger -t duckdns "Initialization succeeded, domain: $DOMAIN.duckdns.org, IP: $NEW_IPV6"
+    else
+        logger -t duckdns "Unable to detect the public IPv6 address"
+        exit 1
+    fi
+fi
+
+
 while true; do
     if CURRENT_IP="$(dig +short myip.opendns.com @208.67.222.222)"; then
         if [ "$CURRENT_IP" != "$(< $LAST_IP)" ]; then
@@ -37,7 +49,23 @@ while true; do
             fi
         fi
     else
-        logger -t duckdns "Unable to detect the public IP address"
+        logger -t duckdns "Unable to detect the public IPv4 address"
+    fi
+    if CURRENT_IPV6="$(dig +short -6 myip.opendns.com aaaa @resolver1.ipv6-sandbox.opendns.com)"; then
+        if [ "$CURRENT_IPV6" != "$(< $LAST_IPV6)" ]; then
+            if RESULT="$(curl -s "https://www.duckdns.org/update?domains=$DOMAIN&token=$TOKEN&ipv6=$CURRENT_IPV6")"; then
+                if [ "$RESULT" = "OK" ]; then
+                    echo "$CURRENT_IPV6" > "$LAST_IPV6"
+                    logger -t duckdns "Update succeeded, new IP: $CURRENT_IPV6"
+                else
+                    logger -t duckdns "Update failed, HTTP API error"
+                fi
+            else
+                logger -t duckdns "Update failed, unable to connect"
+            fi
+        fi
+    else
+        logger -t duckdns "Unable to detect the public IPv6 address"
     fi
     sleep $INTERVAL
 done