cmcurl

#!/bin/sh

# cmcurl: curl shell wrapper to access Arris cable modems on Cox's network
# author: Jan-30-2021, xyntrix@bitz.org
# license: Apache License, Version 2.0
# license-text: https://www.apache.org/licenses/LICENSE-2.0
# intent: Cox Communications installed new firmware on my CPE without notice
#         (as usual). This broke my automated modem status gathering. Wrote
#         this simple shell script to process curl GETS to my cable modem

# requires: curl (and the right password)
# other-notes: arris cert is very expired/invalid.. why even bother with tls?

HASCURL=$(which curl 2>&1 > /dev/null)
if [ ${?} -ne 0 ]; then
  echo "Please install curl."
  exit 1
fi

# cox arris sb8200 cable modem login script
# set following vars to override

# CMLOGIN: always(?) admin
# CMPASS: last 8 digits of serial number (case-sensitive) on modem
#         sticker (NOT mac address)
# CMIP: always(?) 192.168.100.1
# CMURI: uri to access. usually:
#        cm(connectionstatus,eventlog,configuration,
#           address,swinfo,statushelp).html
# CMAUTHURI: uri that provides cred response.. seems to only be this
#             page that parses the auth
# CMPORT: incase this ever changes? otherwise always tcp/443 (disabled for now)
#         ;append to $CMURL
[ -z "${CMLOGIN}" ] && CMLOGIN="admin"
[ -z "${CMPASS}" ] && CMPASS="OMGSECRET111ONE!!1one1!"
[ -z "${CMIP}" ] && CMIP="192.168.100.1"
[ -z "${CMURI}" ] && CMURI="cmconnectionstatus.html"
[ -z "${CMAUTHURI}" ] && CMAUTHURI="cmconnectionstatus.html"
[ ! -z "${CMPORT}" ] && CMIP="${CMIP}:${CMPORT}"

CMURL="https://${CMIP}"

# Create basic auth base64 string of user:pass
AUTH=$(echo -n ${CMLOGIN}:${CMPASS}|base64 -w0)
# send auth as header and as part of uri (weird scheme.. but ok), must go through $CMAUTHURI page
CREDS=$(curl -sk -H "Authorization: Basic ${AUTH}" -H "Content-Type: application/x-www-form-urlencoded; charset=utf-8" ${CMURL}/${CMAUTHURI}?${AUTH})
if [ $? -ne 0 ] || [ ${#CREDS} -gt 40 ]; then
  echo "Error getting creds cookie from: https://${CMIP}/${CMAUTHURI} (${CMLOGIN})"
  exit 1
fi
# now pass creds cookie we received along to GET
# note: this redirects stderr to stdout because i parse it from stdout
curl -sk --cookie "credential=${CREDS}" ${CMURL}/${CMURI} 2>&1