Leap Encryption Access Project

LEAP Encryption Access Project

El Cifrado deberia ser
simple de proveer y facil de usar

Herramientas para comunicaciones seguras en la red
Decentralizar los proveedores de servicios

La Cripto es Dificil

Espera, pero habias dicho...

El Cifrado deberia ser
simple de proveer y facil de usar

asi que...

Solucionemos los Problemas Dificiles

Los “7 Magnificos”

El problema de la Autenticidad
El problema de los Metadatos
El problema de la Asincronicidad
El problema del Grupo
El problema de los Recursos
El problema de la Disponibilidad
El problema de las Actualizaciones

Problema: Autenticidad

La validacion de claves publicas es muy dificil desde el punto de vista de los usuarios, pero sin esto no puedes tener confidencialidad.

Nicknym - auto-descubrimiento y validacion de claves publicas, de forma transparente!

Problema: Metadatos

Los protocolos existentes son vulnerables al analisis de metadatos, pese a que los metadatos son con frecuencia mucho mas sensibles que el contenido.

DNSSEC/DANE a prueba de downgrades

Con uno o mas esquemas oportunistas:

pares de alias automaticos
Onion routing headers
Third party dropbox
Mixmaster con firmas

- DNSSEC: Short term. Opportunistic TLS for email and chat among servers/providers Effective external observers, no protection of user from provider By itself, potential weaknesses to advanced attacks ( timing, traffic analysis ) In the long term, we plan to adopt one of several different schemes for securely routing meta-data. These include: - Auto alias pairs auto negotiate aliases Advantage: backwards compatible Disadvantage: server stores list of aliases - Onion-routing-headers A message from user A to user B is encoded so that the “to” routing information only contains the name of B’s server. When B’s server receives the message, it unwraps (unencrypts) a supplementary header that contains the actual user “B”. Like aliases, this provides no benefit if both users are on the same server. As an improvement, the message could be routed through intermediary servers. - Third party dropbox To exchange messages, user A and user B negotiate a unique “dropbox” URL for depositing messages, potentially using a third party. To send a message, user A would post the message to the “dropbox”. To receive a message, user B would regularly polls this URL to see if there are new messages. - Mixmaster with signatures Messages are bounced through a mixmaster-like set of anonymization relays and then finally delivered to the recipient’s server. The user’s client only displays the message if it is encrypted, has a valid signature, and the user has previously added the sender to a ‘allow list’ (perhaps automatically generated from the list of validated public keys). For a great discussion comparing mix networks and onion routing, see Tom Ritter’s blog post on the topic.

Problema: Asincronicidad

Para las comunicaciones cifradas, tienes que elegir entre forward secrecy o la capacidad de comunicar asincronamente

OpenPGP vs. OTR
A corto: Una capa de transporte forward secrecy sobre OpenPGP
A largo plazo: Colaborar con otros grupos para crear nuevos estandares para protocolos de cifrado

With the pace of growth in digital storage and decryption, forward secrecy is increasingly important. Otherwise, any encrypted communication you engage in today is likely to become cleartext communication in the near future. In the example of email and chat, we have OpenPGP with email and OTR with chat: the former provides asynchronous capabilities, and the latter forward secrecy, but neither one supports both abilities. We need both better security for email and the ability to send/receive offline chat messages. In the short term, we are layering forward secret transport for email and chat relay on top of traditional object encryption (OpenPGP). This approach is identical to our stop-gap approach for the meta-data problem, with the one addition that relaying servers need the ability to not simply negotiate TLS transport, but to also negotiate forward secret ciphers and to prevent a cipher downgrade. This approach is potentially effective against external network observers, but does not achieve forward secrecy from the service providers themselves. In the long term, we plan to work with other groups to create new encryption protocol standards that can be both asynchronous and forward secret. : Forward Secrecy Extensions for OpenPGP Triple elliptical curve Diffie-Hellman handshake

Problema: Grupos

En la practica, trabajamos en grupos, pero... la criptografia de clave publica no.

Lo primero... ummm
Avances interesantes en backup/sync/comparticion segura de archivos (e.g. Wuala and SpiderOak)
Proxy con re-encryptacion
Firmas en anillo

We have a lot of ideas, but we don’t have any solutions yet to fix this. Essentially, the question is how to use existing public key primitives to create strong cryptographic groups, where membership and permissions are based on keys and not arbitrary server-maintained access control lists. Most of the interesting work in this area has been done by companies working on secure file backup/sync/sharing, such as Wuala and Spideroak. Unfortunately, there are not yet any good open protocols or free software packages that can handle group cryptography. ### There is some free software work on some of interesting building blocks that could be useful in building group cryptography. For example: ### - Proxy re-encryption: See Wikipedia This allows the server to re-encrypt to new recipients without gaining access to the cleartext. The SELS mailing list manager (Secure Email List Services) uses OpenPGP to implement a clever scheme for proxy re-encryption. - Ring signatures: See Wikipedia This allows any member of a group to sign, without anyone knowing which member.

Problema: (acceso a) recursos

No existen protocolos abiertos para permitir a los usuarios compartir un recurso

Pues... no les trajimos nada :/
"Read-write-web" les presenta [ponga la solucion al "Group problem" aqui]
De nuevo, mirando hacia el campo del sincronizado de archivos (Lazy Revocation y Key Regression)

Problema: Disponibilidad

Queremos ser capaces de cambiar de dispositivo sin pensarlo, y recuperar nuestros datos si perdemos un dispositivo... pero es dificil hacerlo de forma segura

Soledad - Synchronization of Locally Encrypted Documents Among Devices
vaya! no nos habiamos quedado del todo sin ideas!

Problema: Actualizaciones

De forma casi universal, las actualizaciones de software se hacen de forma que invitan a los ataques y el compromiso de dispositivos

TUF (thanks, Thandy/Tor!)

Gitian en la mira

The sad state of update security is especially troublesome because update attacks can now be purchased off the shelf by repressive regimes. The problem of software update is particular bad on desktop platforms. In the case of mobile and HTML5 apps, the vulnerabilities are not as dire, but the issues are also harder to fix. To address the update problem, LEAP is adopting a unique update system called Thandy from the Tor project. Thandy is complex to manage, but is very effective at preventing known update attacks. Thandy, and the related TUF, are designed to address the many security vulnerabilities in existing software update systems. In one example, other update systems suffer from an inability of the client to confirm that they have the most up-to-date copy, thus opening a huge vulnerability where the attacker simply waits for a security upgrade, prevents the upgrade, and launches an attack exploiting the vulnerability that should have just been fixed. Thandy/TUF provides a unique mechanism for distributing and verifying updates so that no client device will install the wrong update or miss an update without knowing it. Related to the update problem is the backdoor problem: how do you know that an update does not have a backdoor added by the software developers themselves? Probably the best approach is that taken by Gitian, which provides a “deterministic build process to allow multiple builders to create identical binaries”. We hope to adopt Gitian in the future.

Bien, pero... que nos traen hoy?

Servicios

Encrypted Internet Proxy aka VPN - Bitmask 0.6.1

Email - Bitmask 0.7.0

Servicios Planeados

Chat (comenzado)

Client-Encrypted Filehosting

Voip

Collaborative Text Editor

Para usuarias

Bitmask-Client for Linux, Android

OSX, Windows de camino...

Para proveedores

Instalacion y configuracion de servicios "automatica"
Configuraciones de crypto seguras por defecto (parametros TLS, etc)

leap-platform

Recetas Puppet para configurar el servidor


# smtp TLS                                                                    
postfix::config {                                                             
  'smtp_use_tls':        value  => 'yes';                                     
  'smtp_tls_CApath':     value  => '/etc/ssl/certs/';                         
  'smtp_tls_CAfile':     value  => $ca_path;                                  
  'smtp_tls_cert_file':  value  => $cert_path;                                
  'smtp_tls_key_file':   value  => $key_path;                                 
  'smtp_tls_ask_ccert':  value  => 'yes';                                     
  'smtp_tls_loglevel':   value  => '1';                                       
  'smtp_tls_exclude_ciphers':                                                 
    value => 'aNULL, MD5, DES';                                               
  # upstream default is md5 (since 2.5 and older used it), we force sha1      
  'smtp_tls_fingerprint_digest':                                              
    value => 'sha1';                                                          
  'smtp_tls_session_cache_database':                                          
    value => 'btree:${queue_directory}/smtp_cache';                           
  'smtp_tls_security_level':                                                  
    value  => 'may';                                                          
  # see issue #4011                                                           
  'smtp_tls_protocols':                                                       
    value => '!SSLv2, !SSLv3';                                                
}

Configuracion del Proveedor

Server Layout, IPs, contact details, etc


$ cat provider.json 
//
// General service provider configuration.
//
{
  "domain": "example.org",
  "name": {
    "en": "example"
  },
  "description": {
    "en": "You really should change this text"
  },
  "contacts": {
    "default": "admin@example.org"
  },
  "languages": ["en"],
  "default_language": "en",
  "enrollment_policy": "open"
}

$ cat nodes/web1.json 
{
  "ip_address": "99.231.92.23",
  "services": "webapp",
  "tags": "production"
}

Leap-cli

Herramientas de linea de comandos para Admins


$ leap --yes deploy
 Deploying to these nodes: web1, vpn1, couch1
 = updated hiera/couch1.yaml
 = updated hiera/web1.yaml
 = checking node 
   - [web1] ok
   - [couch1] ok
   - [vpn1] ok
 = synching configuration files
   - hiera/web1.yaml -> web1:/etc/leap/hiera.yaml
   - hiera/vpn1.yaml -> vpn1:/etc/leap/hiera.yaml
   - hiera/couch1.yaml -> couch1:/etc/leap/hiera.yaml
   - files/branding/tail.scss, files/branding/head.scss -> web1:/etc/leap
 = synching puppet manifests
   - /home/demo/leap/demo/leap_platform/[bin,puppet] -> web1:/srv/leap
   - /home/demo/leap/demo/leap_platform/[bin,puppet] -> vpn1:/srv/leap
   - /home/demo/leap/demo/leap_platform/[bin,puppet] -> couch1:/srv/leap
...

Instalando un nuevo Proveedor

Inicializacion y puesta en marcha de nuevos nodos

Proveedor de pruebas

demo.bitmask.net - Proveedor de referencia de LEAP

ya abierto para beta testers =)

Proveedores futuros

Etc

para servirles 24/7 en #leap @ irc.freenode.org

Website: https://leap.se

Github Mirror: https://github.com/leapcode

Hecho con reveal.js