http_shield_common.js File Reference

This file contains common functions for Network Boundary Shield. More...

Functions
function	nbsLoadConfiguration ()
function	isIPV4 (url)
function	isIPV6 (url)
function	isIPV4Private (ipAddr)
function	isIPV6Private (ipAddr)
function	parseCSV (csv, ipv4)
function	CSVToArray (strData)
function	expandIPV6 (ip6addr)
function	isNbsWhitelisted (hostname)
function	notifyBlockedRequest (origin, target, tabId)
function	clearNbsNotification (tabId)
function async	createCumulativeNotification (tabId)
function	showNbsNotification (tabId)
function	nbsMessageListener ({message, site}, sender)
	The event listener, hooked up to the webExtension onMessage event.
function	nbsSettingsListener (message)
	The event listener, hooked up to the webExtension onMessage event.
function	nbsCommonMessageListener (message, sender)

Variables
var	localIPV4DNSZones
var	localIPV6DNSZones
var	doNotBlockHosts = {}
var	nbsSettings = {}
var	nbsNotifications = {}
const	NBS_DEF_SETTINGS

Detailed Description

This file contains common functions for Network Boundary Shield.

Author

Copyright (C) 2020 Pavel Pohner

Copyright (C) 2020-2021 Martin Bednář

Copyright (C) 2022 Marek Salon

License:

SPDX-License-Identifier: GPL-3.0-or-later

This file contains basic logic of the NBS, NBS global variables and objects, functions for reading and parsing CSV files, and functions for identifying and processing IP addresses and checking IP ranges.

Function Documentation

clearNbsNotification()

function clearNbsNotification

(

tabId

)

Clear notification data for the tab.

Parameters

tabId

Tab ID of notification.

createCumulativeNotification()

function async createCumulativeNotification

(

tabId

)

Create second notification containing a summary of accumulated data. This notification is shown after the initial one if a page continues to access local network.

Parameters

tabId

Integer number representing ID of browser tab.

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CSVToArray()

function CSVToArray

(

strData

)

Auxillary function for parsing CSV files. Converts CSV to array.

Parameters

strData

Loaded CSV file as a string.

Returns

array containing CSV rows.

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expandIPV6()

function expandIPV6

(

ip6addr

)

Function for expanding shorten ipv6 addresses.

Parameters

ip6addr

Valid ipv6 address.

Returns

expanded ipv6 address in string.

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isIPV4()

function isIPV4

(

url

)

Checks validity of IPv4 addresses.

Parameters

url	An URL that may or may not contains an IPv4 address instead of a domain name.

Returns

TRUE if the url matches IPv4 regex, FALSE otherwise.

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isIPV4Private()

function isIPV4Private

(

ipAddr

)

Checks whether the ipAddr is found in IPv4 localZones. If the IPv4 address is found in any IPv4 local zone, it means that this IPv4 address is private. IPv4 local zone is e.g. 192.168.000.000/16.

Parameters

ipAddr

Valid IPv4 address.

Returns

TRUE if ipAddr exists in localZones fetched from IANA, FALSE otherwise.

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isIPV6()

function isIPV6

(

url

)

Checks validity IPV6 address.

Parameters

url	An URL that may or may not contains an IPv6 address instead of a domain name.

Returns

TRUE, if URL is valid IPV6 address, FALSE otherwise.

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isIPV6Private()

function isIPV6Private

(

ipAddr

)

Checks whether the ipAddr is found in IPv6 localZones. If the IPv6 address is found in any IPv6 local zone, it means that this IPv6 address is private. IPv6 local zone is e.g. fe80::/10.

Parameters

ipAddr

Valid IPv6 address.

Returns

TRUE if ipAddr exists in localZones fetched from IANA, FALSE otherwise.

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isNbsWhitelisted()

function isNbsWhitelisted

(

hostname

)

Check if the hostname or any of it's domains is whitelisted.

Parameters

hostname

Any hostname (subdomains allowed).

Returns

TRUE when domain (or subdomain) is whitelisted, FALSE otherwise.

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nbsCommonMessageListener()

function nbsCommonMessageListener	(		message,
			sender
	)

Event listener hooked up to webExtensions onMessage event. Does appropriate action based on message (e.g. Turn on/off the NBS, add/remove a site to/from whitelist, ...).

Parameters

message	Receives full message.
sender	Sender of the message.

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nbsLoadConfiguration()

function nbsLoadConfiguration

(

)

The function that loads module configuration from sync storage.

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nbsMessageListener()

function nbsMessageListener	(		{message, site},
			sender
	)

The event listener, hooked up to the webExtension onMessage event.

The listener sends message response which contains information if the current site is whitelisted or not.

Parameters

message	Receives full message (destructured as {message, site}).
sender	Sender of the message.

nbsSettingsListener()

function nbsSettingsListener

(

message

)

The event listener, hooked up to the webExtension onMessage event.

The listener sends message response which contains information about cuurent module settings.

Parameters

message

Receives full message.

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notifyBlockedRequest()

function notifyBlockedRequest	(		origin,
			target,
			tabId
	)

Log data about NBS blocking in context of tabs. This data will be used for notification creation.

Parameters

origin	Origin of the request.
target	Target of the request.
tabId	Tab ID of blocked request.

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parseCSV()

function parseCSV	(		csv,
			ipv4
	)

Function for parsing CSV files obtained from IANA. It strips .IN-ADDR and .IP6 from zones and comma delimiter, merges them into array by CSV rows.

Parameters

csv	CSV obtained from IANA.
ipv4	Boolean, saying whether the csv is IPv4 CSV or IPv6.

Returns

an array of parsed CSV values.

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showNbsNotification()

function showNbsNotification

(

tabId

)

Creates and presents notification about blocked requests.

Parameters

tabId

Integer number representing ID of browser tab.

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Variable Documentation

doNotBlockHosts

var doNotBlockHosts = {}

Associtive array of hosts, that are currently among trusted "do not blocked" hosts.

localIPV4DNSZones

var localIPV4DNSZones

Locally served IPV4 DNS zones loaded from IANA.

localIPV6DNSZones

var localIPV6DNSZones

Locally served IPV6 DNS zones loaded from IANA.

NBS_DEF_SETTINGS

const NBS_DEF_SETTINGS

Definition of settings supported by this module.

nbsNotifications

var nbsNotifications = {}

Object holding active notifications of this module.

nbsSettings

var nbsSettings = {}

Associtive array of settings supported by this module.