Andrew Boyson / web

Common stuff for all my devices' web server pages: css, login, log, ipv4, ipv6, firmware update, clock, reset info etc.

Dependents:   oldheating gps motorhome heating

Security

A password has to be set whenever there has been a software reset. Resets following faults or power on do not require a new password as the hash is restored from the RTC GPREG register.

The password is not saved on the device; instead a 32 bit hash of the password is saved. It would take 2^31 attempts to brute force the password: this could be done in under a month if an attempt were possible every millisecond. To prevent this a 200 ms delay is introduced in the reply to the login form, that gives a more reasonable 13 years to brute force the password.

Once the password is accepted a random session id is created. This is 36 bit to give six base 64 characters but without an extra delay. If an attempt could be made every ms then this would still take over a year to brute force.

The most likely attack would to use a dictionary with, say, 10 million entries against the password which would still take 20 days to do.

base/clock/web-clock-script.js

Committer:
andrewboyson
Date:
2019-09-24
Revision:
130:9a5b8fe308f1
Parent:
110:8ab752842d25

File content as of revision 130:9a5b8fe308f1:

//Clock script
'use strict';

let pseudo          = new Clock();
let rtc             = new Clock();

let pseudoDisplay   = false;
let pseudoStartMs   = 0;

let diffMs          = 0;
let rtcIsSet        = false;
let clockIsSet      = false;
let sourceIsOk      = false;
let rateIsLocked    = false;
let timeIsLocked    = false;

let ppb             = 0;
let ppbdivisor      = 0;
let ppbmaxchange    = 0;
let syncedlimitppb  = 0;
let syncedhysppb    = 0;
let slewdivisor     = 0;
let slewmax         = 0;
let syncedlimitns   = 0;
let syncedhysns     = 0;
let maxoffsetsecs   = 0;
let govTrace        = false;

let ntpserver       = '';
let ntpinitial      = 0;
let ntpnormal       = 0;
let ntpretry        = 0;
let ntpoffset       = 0;
let ntpmaxdelay     = 0;

let scanavg         = 0;
let scanmax         = 0;
let scanmin         = 0;

const DISPLAY_LEAP_MS = 10000;

function parseLinesTime(text)
{
    let lines = text.split('\n');
    rtc.ms          = Ajax.date.getTime();
    rtc.ms         += parseInt(lines[0], 16);
    rtc.ms         -= Ajax.ms;
    diffMs          = rtc.ms + Ajax.ms - Date.now();
    rtcIsSet        = Ajax.hexToBit(lines[1], 0);
    clockIsSet      = Ajax.hexToBit(lines[1], 1);
    sourceIsOk      = Ajax.hexToBit(lines[1], 2);
    rateIsLocked    = Ajax.hexToBit(lines[1], 3);
    timeIsLocked    = Ajax.hexToBit(lines[1], 4);
    rtc.leapEnable  = Ajax.hexToBit(lines[1], 5);
    rtc.leapForward = Ajax.hexToBit(lines[1], 6);
    govTrace        = Ajax.hexToBit(lines[1], 7);
    rtc.months1970  = parseInt(lines[2], 16);
    rtc.leaps       = parseInt(lines[3], 16);
}
function parseLinesGov(text)
{
    let lines = text.split('\n');
    ppb             = parseInt(lines[0], 16);
    ppbdivisor      = parseInt(lines[1], 16);
    ppbmaxchange    = parseInt(lines[2], 16);
    syncedlimitppb  = parseInt(lines[3], 16);
    syncedhysppb    = parseInt(lines[4], 16);
    slewdivisor     = parseInt(lines[5], 16);
    slewmax         = parseInt(lines[6], 16);
    syncedlimitns   = parseInt(lines[7], 16);
    syncedhysns     = parseInt(lines[8], 16);
    maxoffsetsecs   = parseInt(lines[9], 16);
}
function parseLinesNtp(text)
{
    let lines = text.split('\n');
    ntpserver       =          lines[0];
    ntpinitial      = parseInt(lines[1], 16);
    ntpnormal       = parseInt(lines[2], 16);
    ntpretry        = parseInt(lines[3], 16);
    ntpoffset       = parseInt(lines[4], 16);
    ntpmaxdelay     = parseInt(lines[5], 16);
}
function parseLinesScan(text)
{
    let lines = text.split('\n');
    scanavg         = parseInt(lines[0], 16);
    scanmax         = parseInt(lines[1], 16);
    scanmin         = parseInt(lines[2], 16);
}
function parse()
{
    let topics = Ajax.response.split('\f');
    parseLinesTime(topics[0]);
    parseLinesGov (topics[1]);
    parseLinesNtp (topics[2]);
    parseLinesScan(topics[3]);
}
function display()
{
    let elem;
    elem = Ajax.getElementOrNull('ajax-rtc-set'      ); if (elem) elem.setAttribute('dir', rtcIsSet     ? 'rtl' : 'ltr');
    elem = Ajax.getElementOrNull('ajax-clock-set'    ); if (elem) elem.setAttribute('dir', clockIsSet   ? 'rtl' : 'ltr');
    elem = Ajax.getElementOrNull('ajax-source-ok'    ); if (elem) elem.setAttribute('dir', sourceIsOk   ? 'rtl' : 'ltr');
    elem = Ajax.getElementOrNull('ajax-rate-locked'  ); if (elem) elem.setAttribute('dir', rateIsLocked ? 'rtl' : 'ltr');
    elem = Ajax.getElementOrNull('ajax-time-locked'  ); if (elem) elem.setAttribute('dir', timeIsLocked ? 'rtl' : 'ltr');
    
    elem = Ajax.getElementOrNull('ajax-leap-enable'  ); if (elem) elem.setAttribute('dir', rtc.leapEnable   ? 'rtl' : 'ltr');
    elem = Ajax.getElementOrNull('ajax-leap-forward' ); if (elem) elem.setAttribute('dir', rtc.leapForward  ? 'rtl' : 'ltr');
    
    elem = Ajax.getElementOrNull('ajax-leap-year'    ); if (elem) elem.value = rtc.months1970 ? rtc.leapYear  : '';
    elem = Ajax.getElementOrNull('ajax-leap-month'   ); if (elem) elem.value = rtc.months1970 ? rtc.leapMonth : '';
    
    elem = Ajax.getElementOrNull('ajax-leap-count'   ); if (elem) elem.value = rtc.leaps;
    
    elem = Ajax.getElementOrNull('ajax-ppb'          ); if (elem) elem.value = ppb;
    elem = Ajax.getElementOrNull('ajax-ppb-divisor'  ); if (elem) elem.value = ppbdivisor;
    elem = Ajax.getElementOrNull('ajax-ppb-max-chg'  ); if (elem) elem.value = ppbmaxchange;
    elem = Ajax.getElementOrNull('ajax-ppb-syn-lim'  ); if (elem) elem.value = syncedlimitppb;
    elem = Ajax.getElementOrNull('ajax-ppb-syn-hys'  ); if (elem) elem.value = syncedhysppb;
    elem = Ajax.getElementOrNull('ajax-off-divisor'  ); if (elem) elem.value = slewdivisor;
    elem = Ajax.getElementOrNull('ajax-off-max'      ); if (elem) elem.value = slewmax;
    elem = Ajax.getElementOrNull('ajax-off-syn-lim'  ); if (elem) elem.value = syncedlimitns / 1000000;
    elem = Ajax.getElementOrNull('ajax-off-syn-hys'  ); if (elem) elem.value = syncedhysns   / 1000000;
    elem = Ajax.getElementOrNull('ajax-off-rst-lim'  ); if (elem) elem.value = maxoffsetsecs;
    elem = Ajax.getElementOrNull('ajax-gov-trace'    ); if (elem) elem.setAttribute('dir', govTrace     ? 'rtl' : 'ltr');
    
    elem = Ajax.getElementOrNull('ajax-ntp-server'   ); if (elem) elem.value = ntpserver;
    elem = Ajax.getElementOrNull('ajax-ntp-initial'  ); if (elem) elem.value = ntpinitial;
    elem = Ajax.getElementOrNull('ajax-ntp-normal'   ); if (elem) elem.value = ntpnormal / 60;
    elem = Ajax.getElementOrNull('ajax-ntp-retry'    ); if (elem) elem.value = ntpretry;
    elem = Ajax.getElementOrNull('ajax-ntp-offset'   ); if (elem) elem.value = ntpoffset;
    elem = Ajax.getElementOrNull('ajax-ntp-max-delay'); if (elem) elem.value = ntpmaxdelay;
    
    elem = Ajax.getElementOrNull('ajax-scan-avg'     ); if (elem) elem.textContent = scanavg;
    elem = Ajax.getElementOrNull('ajax-scan-max'     ); if (elem) elem.textContent = scanmax;
    elem = Ajax.getElementOrNull('ajax-scan-min'     ); if (elem) elem.textContent = scanmin;
    
    elem = Ajax.getElementOrNull('ajax-date-diff'    ); if (elem) elem.textContent = diffMs;
}

function handleTick() //This typically called every 100ms
{
    if (pseudoDisplay)
    {
        pseudo.adjustLeap (Ajax.ms);
        pseudo.displayTime(Ajax.ms);
        if (Ajax.ms >= pseudoStartMs + DISPLAY_LEAP_MS + 500) pseudoDisplay = false;
    }
    else
    {
        rtc.adjustLeap (Ajax.ms);
        rtc.displayTime(Ajax.ms);
    }
}

function displayLeap() //Called by display leap button in HTML
{
   pseudoDisplay = true;
   pseudoStartMs = Ajax.ms;
   
   pseudo.leapEnable  = true;
   pseudo.leapForward = rtc.leapForward;
   pseudo.leaps       = rtc.leaps;
   pseudo.leapMonth   = rtc.leapMonth;
   pseudo.leapYear    = rtc.leapYear;
   pseudo.ms          = Date.UTC(rtc.leapYear, rtc.leapMonth - 1, 1) - DISPLAY_LEAP_MS / 2 - Ajax.ms;
}
Ajax.server     = '/clock-ajax';
Ajax.onResponse = function() { parse(); display(); };
Ajax.onTick     = handleTick;
Ajax.init();