10. Security and user interface

EPKeygen

https://gyazo.com/b613461e4759af40dcbd1950a5f0a4d3

Twitter takeover incident (2017)

https://gyazo.com/4fd4b80773fe58d40b65bbad5daeb82e

Usability and security

Tradeoff exists

Important, but not popular

Think about security issues from a wider view

システム/人間を総合的にセキュリティを考える

重要概念だが流行っていない

必要技術

人が安心できる方式

安全性を評価する技術

https://gyazo.com/a082e9d54a3f2e778c516bb82c47a376.png

Think about security from psychological aspect

Since 2011

Number of people ar small

Research on Security

Cryptography, attacks, valunarability, ...

社会における様々な機能がインターネットやそこに接続された無数のコンピュータによって制御され、運用管理が行われるようになった現在、ネットワークで接続されたサイバースペースの安全は今後の社会を支えていく上でますます重要なものとなっている。日々様々な形の犯罪や事故が発生しておりこういった事態を未然に防止し被害を最小に止めるサイバーセキュリティの専門家に対するニーズが高まっている。セキュリティ専門家は情報技術やネットワークの技術的な知識だけでなく、法律、社会制度、組織の運営管理など学際的で総合的な知識に加えサイバー攻撃やシステム脆弱性の分析、事件・事故への迅速な対処などセキュリティ領域における深い理解と高度な対処能力も求められる。本コースでは、 SFCの学際性と情報通信分野における高度な専門性を活かして社会の要請に応える高度なサイバーセキュリティ人材を育成する。

Cyber leadership course (Prof. Nakamura)

https://gyazo.com/52014c00ff1fa1871055ae1bd7be3838

WHat is the right authentication approach?

https://gyazo.com/dc4a183e4c4854480e590c09fcb5e40b

https://gyazo.com/12e4b11d6ce50f83514d8a1e7b1b82cd

Security visualizaton

https://www.amazon.co.jp/dp/0321510100 https://gyazo.com/7aedb3bff6f9ce6ecb04ff6ab23b32af

Reason why we need authentication

Ubiquitous society

→ Everybody uses computers anywhere

→ Computers ared shared by many people

→ Authentication required everywhere

Authentication methods

What we have

Keys, USB devices

What we are

Biometric authentication (fingerprint, etc.)

What we know

Passwords, challenge questions

What we can do

CAPTCHA

Combination of above methods

Bank card + PIN

2-factor authentication

Biometric authentication + PIN

Authentication on the Web

Mainly password-based

Ather authentication methods are rarely used

Password authentication

Easy to implement

No recognition systems required

Easy to use on PC

Using keyboards

Secure if properly managed

Can be strong with very long passwords

Problems of password authentication

Difficult to choose an appropriate password

Difficult to remember

Easily forgotten

Easily attacked

Easily copied

Text input device required

Problems of authentication hardware

(Like keys, cards, etc.)

Inconvenient to carry

Forget to carry

Risk of theft or loss

Problems of biometric authentication

Unusable when sick or injured

Can be copied

Can be used by stunning

Can't change data

Comparison of various authentication techniques

Passwords might be the best

http://gyazz.com/upload/be36ee9a3c80239387aea5e5776de6f5.pdf https://gyazo.com/dae200eef4281fe3b8e4f8dc6c9b44b9.png

Managing passwords

Password reuse is very risky

https://gyazo.com/4f1e7b5e4442fb9e71683c859632ccde

Password management

Frequent change of password is not recommended

People tend to use simpler passwords

Ok if people change it voluntarily

Writing down on paper may be okay

Checking if your password is known

Chrome extension

Warned when we try to use a stolen password

Check examplle

Authentication on browsers

Basic authentication

Digest authentication

Proprietary methods

Basic authentication (Apache)

code:.htaccess

AuthUserFile /home/masui/.htpasswd

AuthGroupFile /dev/null

AuthName "Password Required"

AuthType Basic

require user masui

Passwords are sent to the server in plain text

code:.htaccess

AuthType Digest

AuthName "member only"

AuthDigestDomain /server/script/digest/

AuthDigestFile /home/masui/.htdigest

require user masui

Encrypted passwords sent to server

Encryption is based on an ID give by server

Use special authentication technique

code:html

<center>

<input type="password" style="font-size:30pt;"><br>

<span style="font-size:24pt;"><input type="password" style="font-size:20pt;"></span>

</center>

Communication via HTTPS

Prevent peeking

How to continue login status

Use "cookies"

Send auth data every time browser interact with server

Authentication on the Web

PKI (Public Key Infrastructure)

PGP (Pretty Good Privacy)

c.f. Certificate authority in the real world

https://gyazo.com/58ba83f7368ca767ab28ffb25a368d1f.png

Notary

Publish certificate document (deed)

Give credential to personal documents

Prove the fixed date to data

City hall

PKI

https://gyazo.com/0647da8a7628a2081e047edfa16b4473.png

Prevent the risk of losing secret key

pk⇒sk、sk⇒pk cannot be calculated

m == Dsk(Epk(x))

Using ssh

Copy public key to server

Keep secret key in PC

Public key should be treated carefully

Demo: ssh

% ssh-keygen

SSL

Secure Sockets Layer

Developed by Netscape in 1994

Used for secure communication between browser and server

https://(url)

Characteristics of public-key cryptography

Secure communication using shared public key

Public key should be examined before starting communication

Cirtificate Authority (CA)

Guarantee that the public key is correct

Publish certificate

If we can trust the CA, we can trust the public key guaranteed by the CA

Public keys of the CAs should be guaranteed

Registered on browsers

https://gyazo.com/9e9b7d53ce5f24737b725fcbe197a858.png

CA hiearachical structure

https://gyazo.com/d3abed0b5c711d0bd2106c9facc4a53e.png

Certificate published by the user

Not registered in browsers

No money paid to CA

Difficulty of proving whether the data is right

Data can be easily copied and created from scratch

e.g. Difficult to prove that certain data existed at a specified time

Use notary office

Electric notarization

Problems of electric notarization

Takes time

Costs a lot

Not easily usable

Register information (and its hash value) at many places

Maybe used for proving the date

Digital timestamp technology and services

Authentication topics related to time

Can you create data tha can be available only after 2 years?

Don't use centeral CAs

People believe the data if the data is signed by many people

Web authentication services

FlickrAPI

TypeKey authentication

Hatena authentication API

livedoor Auth

JugemKey authentication API

Facebook OAuth

特定サービスにパスワードを教えることなくFlickerにアクセスさせる

Flickerのパスワードで別のサービスを利用する

https://gyazo.com/5575fb6404ab2b6f6913944dfbc4456f.png

はてなアカウントによる認証を別サイトで利用

アカウント管理をはてなにアウトソーシング

知名度向上や新規ユーザ獲得を期待

https://i.gyazo.com/8c320e4e21bc931f824736189f9f0b7c.png

Problems of OpenID

https://i.gyazo.com/c545180dc113d2aaab03a2d664489bb0.png

Many services from many providers

Confusing

Standardization of authentication services

OpenID

OAath

Basic technology

Single Sign-On (SSO)

Authentication and Autorization

Authentication (認証)

Authorization (認可)

Authentication (認証)

Check if the right user is accessing the network

Using ID and passwords

If successful, all data can be managed by the login user

Authorization

Control access rights based on the authentication information

Possible to allow partial access

Use outside service for authentication

No need to handle password in the service

Single sign-on standard

Authentication for the Web

Authentication only

(no authorization)

Commponents in OpenID

OP（OpenID Provider）

Authentication service provider

RP（Relying Party）

Web service that use OpenID authenticator

OpenID account

Users

OpenID protocol

https://i.gyazo.com/98a5e827a405bd8d1192b65b6fd20700.png

OpenI protocol

https://i.gyazo.com/25c180ad66415d47e5f6337848aa3e6d.png

OpenID providers

https://gyazo.com/9b06c996489f365ae5daffd8a94c77f7.png

その他多数

code:html

<html>

<head>

<link rel="openid.server"

<link rel="openid.delegate"

Log in at a service that support OpenID

Enter ID and password in vox authentication window

OpenID providers

Usability of OpenID

Registration and setting up difficult

Difficult to underestand the principle

Difficult to enter ID

Current status

Less number of people are using

Non-smart specification

Concerns

Is it okay to use outside service for passwor management?

We cannot tell if service provider is reliable

Introduced in 2007

Authorization protocol

Useful for "mushup" services

Users allow the usage of their data to other services

e.g. allow a service to use Facebook data

Consumer (e.g. smart.fm) asks service provider (e.g. Google) to get access token

VERY complicated

https://gyazo.com/02a7c417784367f814663dd9021f1056.png

0. ConsumerはService ProviderからあらかじめOAuth利用許可を得る

1. UserがConsumerに，Service Providerから認可が必要な情報へのアクセス権を取得するように指示する。

2. ConsumerはバックグラウンドでService Providerにアクセスし，未認可のRequest Tokenを取得する

3. ConsumerはUserをService Providerにリダイレクトさせる。この際Consumerは未認可のRequest TokenをURL Parameterに付加する

4. UserはService Provider上でConsumerへのアクセス権委譲を許可する。この際Service Providerは未認可のRequest Tokenを認可済とする

5. Service ProviderはUserをConsumerにリダイレクトさせる。この際Service Providerは認可済のRequest TokenをURLに含める

6. ConsumerはバックグラウンドでService Providerと通信を行い，認可済のRequest Tokenを実際のアクセス権を示すAccess Tokenと交換する

7. Consumerは6)で得られたTokenを利用して，特定の情報にアクセスする</span><br>

OAuth example

https://gyazo.com/e5154feec4faf9726a793a39baff7068.png

OpenID vs OAuth

https://gyazo.com/907f74bfce4340a058081fca4f277ccf

Problems of authorization services

Difficult to understand the principle

Can anybody understand concepts?

Can people notice flaud?

Not very easy to use

Phishing possibilities

Toward ideal authentication interface

Everybody

Everywhere

Easy

Safe

c.f. Safety(安全) and peace of mind (安心)

Safety = objective

Peace of mind = subjective

Safety

No fatal risk

Not safe but feels safe

Car driving

Password

Keys

Safe but feels unsafe

Chemical ingredient

PKI?

Something with safe feeling

Understandable

Familiar

Old

Problems of password authentication (再掲)

Difficult to choose an appropriate password

Difficult to remember

Easily forgotten

Easily attacked

Easily copied

Text input device required

Problems of authentication hardware

(Like keys, cards, etc.)

Inconvenient to carry

Forget to carry

Risk of theft or loss

Problems of biometric authentication

Unusable when sick or injured

Can be copied

Can be used by stunning

Can't change data

Password management systems

Handle multiple passwords in a single application

Users should remember a "master passwords"

Fatal if they forget it

Not the best solution, but practical solution

Password management systems

1Password

LastPass

Just1Key

SuperGenPass

Dashlane

Enpass

SplashID

KeePass

Keeper

...

Two-step authentication

Use SMS and phone to double-check

Losing smartphone might be fatal

"Recovery code" required, but difficult to manage them

Ideal authentication system

Safe

Feel safe

Available anywhere

No need to think a lot

No need to remember something

No need to use special devices

Requirements

Knowledge, ability, ...

c.f. semantic memory

Everybody has episodic memories

Never forget

Other people cannot guess

Cannot be copied

Why not using episoic memories for authentication?

Image-based authentication

Use images for authentication

Use images related to memories

Draw special images

Recommending image-based authentication

Article on image-based authentication

IPSJ Journal (情報処理) vol.47, no.5 (2006)

Draw-A-Secret (DAS)

Gesture recognition

http://gyazo.com/c8b5733cb850b946e8bfea27dc3fd518.png

DéjàVu

Select your favorite images

Images are automatically created

https://gyazo.com/38a52f9d4f2c67eaf6f6cc7acdf3e13e.png

Select faces you like

https://gyazo.com/918210f59d3892b2acdeb7aa276e9863.png

Mnemonic guard

https://www.axseed.co.jp/?page_id=287 https://gyazo.com/7c556f3b48c57da14dcd2868a63b64fa

LockTile

https://gyazo.com/d819ab10b299cc8cb8769b81ff342a8c

Select special points in an image

https://gyazo.com/2dbb4edc510938f3f23a0811e6b12ea6.png

PassPoints

https://gyazo.com/eb52cc445b41c141dae0c2425b962d19.png

Remember categories

Select an image related to the category

https://gyazo.com/a5e94fe05d651e09b942566eba50684b.png

Triangle-based image authentication

Draw a triangle that surrounds the icon you want to choose

Prevent sholder hacking

https://gyazo.com/351a3b2722a7f524c2271812f07308c5.png

Shoulder hacking

https://gyazo.com/324af4ef486afe640be3e0268010f19e

GATESCEME

https://gyazo.com/81ebd8dd7d8957b7a8418f515d42f7e9.png

Remember combination of images and numbers

Recall-a-Story

https://gyazo.com/80cf70536ce29eb3e8afcde8e93f30f6.png

Remember a story, and select items based on the story

MARASIM

https://gyazo.com/7cc969827bd1b4d58449afc0b6daeafa.png

Remember a special image

Select images related to the special image

https://gyazo.com/75adce63e0ef68b5e2e41aac155cab96.png

潜在記憶を利用するもの

https://gyazo.com/936884a1c4ed1dfec042c2e2d5fb501b.png

Problems of image-based authentication

Difficult to keep memory

Not easy to perform authentication

QA-based image authentication

Select right answers for personal images

Authentication success when all the answers are correct

Demo: Hondana.org

Advantages of QA-based image authentication

Difficult to forget answers

Easy to select an answer

Can be used in a specific group

Problems of QA-based image authentication

Difficult to create questions

Not feel safe

Generate a password string from episodic memories

Convert a "seed string" based on the answers and generate a password string

http://EpisoPass.com https://gyazo.com/795316ca9f1305f4e41c5f095a0197e0.png

EpisoPass questions

EpisoPass chrome extension

Available for Amazon, Twitter, etc.

No need to enter passwords

Demo: Masui's passwords

Advantages of EpisoPass

All the data can be put in public places

Never lose the password data

Never forget passwords

Available on any machine that have a Web browser

Tips for creating questons

Create a list of answers

Names of places

Names of people you know

Then create a question that describes one entry

e.g. "Where was the scary mountain?"

Questions can be created easily from answers

Authentication and human factor

Many researchers working on safety issues

Strength of cryptography techniques

Authentication protocols

Few people working on human factor in authentication

How to feel safe

How to run safe systems

How can we feel safe?

We should understand the basics before feeling safe

Passwords

Cryptography

Public-key method

Certificate authority

OpenID basics

Difficult to understand the logic

⇒ Cannot feel safe

Authentication systems should be easy to use

Installation

Everyday use

Tradeoff between usability and security

Operation problems

Too much secret information on PC

Passwords on browser

Secret keys

Risk of theft very large

When your PC is stolen, you lose everything

Solution: EPKeygen

Generate secret string using EpisoPass interface

Demo: EPKeygen

Future outlook

Better authentication services emerge

Simple, usable authentication methods

http://mypico.org/ http://gyazo.com/deca5de3a60363eaa7d6b14a70f5ca5c.png

A Progect at Cambridge University

Masui joined the team in 2016

Use a special hardware to solve the password problems

Video: Pico

https://vimeo.com/82448991