Szia!
Kicsit keresgéltem ez ügyben. 
Ezt találtam, nekem úgy tűnik működik a Vargalex féle Openwrt alatt.
Legalábbis a script futtatása után ezt a választ kapom:
...
+ echo Login successful
Login successful
+ exit 0
Csak a curl-t kellett telepíteni hozzá.
És a script:
#!/bin/sh
#DEBUG=1
LOGIN="****"
PASSWORD="****"
COOKIES="/tmp/.dynsdns.cookies.txt"
AL="en-gb"
#UA="Mozilla/5.0 (Macintosh; Intel Mac OS X) AppleWebKit/0.0.0 (KHTML, like Gecko) Version/0.0.0 Safari/0.0.0"
LOGINURL="https://account.dyn.com/entrance/"
POSTURL="$LOGINURL"
CHKURL="https://account.dyn.com/"
(( $DEBUG )) && DST="-" || DST="/dev/null"
[[ -w "$( dirname "$COOKIES" )" ]] || { echo >&2 "FATAL: Cannot write to directory '$( dirname "$COOKIES" )'" ; exit 1; }
# Ensure no broken session caching...
if [[ -s "$COOKIES" ]]; then
[[ -w "$COOKIES" ]] || { echo >&2 "FATAL: Cannot write to file '$COOKIES'" ; exit 1 ; }
rm -f "$COOKIES" >/dev/null 2>&1
fi
(( $DEBUG )) && echo >&2 "DEBUG: Fetching initial headers to pre-load cookies..."
curl -b $COOKIES -c $COOKIES -Ikso "$DST" -A "$UA" --url "$LOGINURL"
(( $DEBUG )) && echo >&2 "DEBUG: Fetching UID..."
VALUE="$(
curl -b $COOKIES -c $COOKIES -kso - -A "$UA" --url "$LOGINURL" | \
grep -m 1 "multiform" | \
cut -d"'" -f 6
)"
(( $DEBUG )) && echo >&2 "DEBUG: Read UID as '$VALUE' - posting data..."
curl -b $COOKIES -c $COOKIES -d "username=$LOGIN" -d "password=$PASSWORD" -d "iov_id" -d "multiform=$VALUE" -e "$LOGINURL" -kso "$DST" -A "$UA" --url "$POSTURL"
(( $DEBUG )) && echo >&2 "DEBUG: Response received - verifying result..."
curl -b $COOKIES -c $COOKIES -e "$POSTURL" -kso - -A "$UA" -H "Accept-Language: $AL" --url "$CHKURL" | \
grep -qE "<span>(Welcome|Hi) <b>$LOGIN</b></span>" \
&& echo "Login successful" \
|| { echo >&2 "Login failed" ; exit 1 ; }
exit 0
Forrás:[link]
Steve
