https: all you need to know

HTTPSAll you need to know

Vincent Cassé @vcasse

Webhosting lead techOVH

Why HTTPS?

To protect your data

To protect your data

To protect your data

To protect your data

To protect your data

To authenticate the source

To authenticate the source

Check integrity of the data Don’t change the HTTP protocol

Why HTTPS too?

How HTTPSworks?

Crypto basics: symmetric encryption

Crypto basics: asymmetric encryption

Crypto basics: asymmetric encryption

Crypto basics: asymmetric encryption

Crypto basics: asymmetric encryption

Crypto basics: digital signature

Crypto basics: digital signature

Crypto basics: digital signature

$ echo "OVH" |  sha1sum3b4e44a27f4652afa4490c300e35b320f0849a96  ­

$ echo "OV H" | sha1sum7d916134d9c1ce2ecce3326ffb39ac1612535366  ­

$ curl "https://ovh.com/fr" | sha1sum479855683ee2249a9e6be690805ff29d04bdcb95  ­

Crypto basics: digital signature with key

Crypto basics: digital signature with key

Crypto basics

HTTPS: how does it work?

HTTPS: how does it work?

HTTPS: how does it work?

HTTPS: how does it work?

openssl req  ­new ­sha256 \­newkey rsa:2048 \­keyout mydomain.com.key \­out mydomain.com.csr \­subj /countryName="FR"/commonName="mydomain.com"/

HTTPS: how does it work?

HTTPS: how does it work?

CA: can you trust it?

Certification Authority can have issues (bugs / hacks) ~1800 CAs around the world (government, firms...) Each CA can generate certificates for all domains CA can cheat (StartSSL & SHA-1 certificate)

DANE: solution for CA issues?

RFC 6698 Publish certificate into the DNS With DNSSEC, attack perimeter reduced

But: no browser check it

Certificates types

Single: contains only one domain SAN: can contain multiple domains (subdomain or multidomain) Wildcard: can contain one domain and validate all their subdomains

DV: Domain validation

Check ownership of domain Validation method: HTTP / DNS / email Green lock in browsers Doesn’t block typosquatting

OV: Organisation validation

DV validation Check if your organization is real (siret) Same green lock as DV in browsers

EV: Extended validation

DV validation + OV validation Contact multiple people inside your entreprise Green bar in browser Customer can trust this certificate to pay online

How useHTTPS?

SNI

RFC 6066 Allow multiple certificates by IP Some browsers don’t handle it

Android 2.xx Java 6 IE on Windows XP

Protocol

Define exchange between server and browser From SSLv2 in 1994 to TLS1.3 (work in progress) SSLv2 and v3 are deprecated. TLS1.0 is end of life

Protocol: browser compatibility

SSLv2, SSLv3, TLS1.0: all browser understand TLS1.1: All without IE ≤ 8 and Android ≤ 4.4.4 TLS1.2: All without IE ≤ 8 and Android ≤ 4.4.4 ChaCha20-Poly1305 : Only firefox, chrome and android > 5.0

Protocol: hacking

SSLv3 vulnerable to POODLE attack TLS is attacked on weak algo : RC4 / SHA-1 TLS is attacked on renegotiation to SSLv2

Cipher suites

TLS_RSA_WITH_AES_256_CBC_SHA TLS_RSA_WITH_AES_256_CBC_SHA256 TLS_ECDH_ECDSA_WITH_AES_128_CBC_SHA TLS_ECDH_ECDSA_WITH_AES_256_CBC_SHA TLS_ECDH_ECDSA_WITH_RC4_128_SHA TLS_ECDH_ECDSA_WITH_DES_CBC_SHA

Cipher suites: hacking

DES / 3DES too weak RC4 / MD5 / SHA-1 too weak RSA < 2048bits too weak

https://wiki.mozilla.org/Security/Server_Side_TLS

Mixed Content

Browser alerts about HTTP « passive content » (images/video…) Browser blocks HTTP « active content » (css/javascript)

HSTS

Header set Strict­Transport­Security "max­age=10886400; includeSubDomains;" env=HTTPS

Why do I needHTTPS?

Protect your customers

No account thef No credit card thef Your customers trust you

SEO

Google prefers HTTPS websites And other search engines too

Browsers will kill HTTP

HTTP will be flagged as unsecure In the next years, customer will stop going to your website

HTML5

Browsers had to use HTTPS to enable some HTML5 APIs

getUserMediaservice workersencrypted Media Extension

HTTP2

Browsers had to use HTTPS to enable HTTP2 Multiplex HTTP requests and responses Compress TCP stream

Just fastest than HTTPS

OVHcan help me?

WebHosting

SSL included with all offers DV / EV validated by Comodo as an option

Validation / Type / Installation / Renew handled for you

SSL gateway

Validation / Installation / Renew handled for your servers No more maintenance Just update your domain then add your server as backend and you

will be SSL compliant

Some links

https://paulgreg.me/https-slides/?full#html5-seo https://www.feistyduck.com/ssl-tls-and-pki-history/ http://www.flaticon.com https://www.ssllabs.com/

Vincent Cassé

@vcasse