# Presentation: 470007

## Crossing the Styx:Taming the Underworld Using Cerberus and PlutoPlus(ITL’s Contributions in the Area of Internet Security)

**Sheila Frankel**
**Systems and Network Security Group, ITL**

## Unsolved Problems of the 1990s

- World Peace
- A Drinkable Diet Cola
- Secure Communications over an Insecure Network

## Types of Security Protection

- Data Origin Authentication
- Connectionless Integrity
- Replay Protection
- Confidentiality (Encryption)
- Traffic Flow Confidentiality

## At Which Network Layer Should Security Be Provided?

- Application Layer
- Transport (Sockets) Layer
- Internet Layer

## Why Internet Layer Security?

- Implement once, in a consistent manner, for multiple applications
- Centrally-controlled access policy
- Enable multi-level, layered approach to security

## Internet Packet Format

**IP**
**Header**

**Upper Protocol Headers**
**and Packet Data**

## Authentication Header (AH)

- Data origin authentication
- Connectionless integrity
- Replay protection (optional)
- Transport or tunnel mode
- Mandatory algorithms:
- HMAC-MD5
- HMAC-SHA1
- Other algorithms optional

## Internet Packet Format with AH

**IP**
**Header**

**AH**
**Header**

**Upper Protocol Headers**
**and Packet Data**

- Tunnel Mode

- Transport Mode

## Encapsulating Security Payload (ESP)

- Confidentiality
- Limited traffic flow confidentiality (tunnel mode only)
- Data origin authentication
- Connectionless integrity
- Replay protection (optional)
- Transport or tunnel mode

## Encapsulating Security Payload (ESP) (cont’d)

- Mandatory algorithms:
- DES-CBC
- HMAC-MD5
- HMAC-SHA1
- Other algorithms optional

## Internet Packet Format with ESP

**IP**
**Header**

**ESP**
**Header**

**Upper Protocol Headers**
**and Packet Data**

- Tunnel Mode

**New IP**
**Header**

**Old IP**
**Header**

**ESP**
**Header**

**Upper Protocol Headers**
**and Packet Data**

- Transport Mode

## Transport vs. Tunnel Mode

## Constructs Underlying IP Security

- Security Association (SA)
- Security Association Database (SAD)
- Security Parameter Index (SPI)

## Internet Key Exchange (IKE)

- Negotiate:
- Communication Parameters
- Security Features
- Authenticate Communicating Peer
- Protect Identity
- Generate, Exchange, and Establish Keys in a Secure Manner
- Delete Security Associations

## Internet Key Exchange (IKE) (cont’d)

- Threat Mitigation
- Denial of Service
- Replay
- Man in Middle
- Perfect Forward Secrecy
- Usable by Ipsec and other domains (e.g., private keys for VPNs)

## Internet Key Exchange (IKE) (cont’d)

- Components:
- Internet Security Association and Key Management Protocol (ISAKMP)
- Internet Key Exchange (IKE, aka ISAKMP/Oakley)
- IP Security Domain of Interpretation (IPsec DOI)

## IKE Negotiations - Phase 1

- Purpose:
- Establish ISAKMP SA (“Secure Channel”)
- Steps (4-6 messages exchanged):
- Negotiate Security Parameters
- Diffie-Hellman Exchange
- Authenticate Identities
- Main Mode vs. Aggressive Mode

## IKE Negotiations - Phase 2

- Purpose:
- Establish IPsec SA
- Steps (3-5 messages exchanged):
- Negotiate Security Parameters
- Optional Diffie-Hellman Exchange
- Final Verification
- Quick Mode

## IKE Network Placement

**DOI**
**Definition**

**Security Protocol**
**(IPsec)**

**Application Protocol**

**Application Process**

**IKE**

## IKE Peer Negotiation

**Application**

**IKE**

**Application**

**IKE**

- Application Space

- Application Space

- Kernel Space

- Kernel Space

**IPSEC**

**IPSEC**

**Physical Network**

**1**

**2**

**4**

**3**

**3**

**5**

**4**

**5**

## Current Status of IPsec

- Most documents in Internet-Draft last call, headed for RFC status
- IPsec Working Group disbanded
- IPsecond Working Group starting up
- Multiple implementations (Sun, IBM, Microsoft, DEC, Cisco, Telebit, others) deployed, in beta test, or under development

## Current Status of Ipsec (cont’d)

- Periodic interoperability/conformance testing using reference implementations
- Auto Industry eXchange (ANX) pushing for early deployment
- PKI work underway in IETF, industry, government (NIST et. al.)

## The IETF’s Direction in IP Security

- IETF has mandated use of IPsec and IKE wherever feasible
- Testing support needed for emerging implementations
- Need publicly-available sites that are willing to provide IPsec testing
- Requested at 38th IETF meeting

## NIST’s Contributions to IPsec

- Cerberus - Linux-based reference implementation of Ipsec
- (http://snad.ncsl.nist.gov/cerberus)
- PlutoPlus - Linux-based reference implementation of IKE
- IPsec-WIT - Web-based IPsec interoperability test facility
- (http://ipsec-wit.antd.nist.gov)

## NIST’s Contributions to IPsec (cont’d)

- Goals:
- Enable smaller industry vendors to jump-start their entry into IPsec
- Facilitate ongoing interoperability testing of multiple IPsec implementations

## IPsec - Missing Pieces

- Policy specification and control
- Communication with CAs

## IPsec Internet Drafts - Basic Documents

- IP Security Document Roadmap
- (draft-ietf-ipsec-doc-roadmap-02.txt)
- Security Architecture for the Internet Protocol (draft-ietf-ipsec-arch-sec-04.txt)
- IP Authentication Header
- (draft-ietf-ipsec-auth-header-05.txt)
- IP Encapsulating Security Payload (ESP) (draft-ietf-ipsec-esp-v2-04.txt)

## IPsec Internet Drafts  - Authentication Algorithms

- The Use of HMAC-MD5-96 within ESP and AH (draft-ietf-ipsec-auth-hmac-md5-96-03.txt)
- The Use of HMAC-SHA-1-96 within ESP and AH (draft-ietf-ipsec-auth-hmac-sha1-96-03.txt)
- The Use of HMAC-RIPEMD-160-96 within ESP and AH
- (draft-ietf-ipsec-auth-hmac-ripemd-160-96-01.txt)

## IPsec Internet Drafts  -Cryptographic Transforms

- The ESP ARCFOUR Algorithm
- (draft-ietf-ipsec-ciph-arcfour-00.txt)
- The ESP Blowfish-CBC Algorithm Using an Explicit IV
- (draft-ietf-ipsec-ciph-blowfish-cbc-00.txt)
- The ESP CAST128-CBC Algorithm
- (draft-ietf-ipsec-ciph-cast128-cbc-00.txt)
- The ESP CAST5-128-CBC Transform
- (draft-ietf-ipsec-ciph-cast-div-00.txt)

## IPsec Internet Drafts - Cryptographic Transforms (cont’d)

- The ESP CBC-Mode Cipher Algorithms
- (draft-ietf-ipsec-ciph-cbc-02.txt)
- ESP with Cipher Block Chaining (CBC)
- (draft-ietf-ipsec-cbc-00.txt)
- The ESP DES-CBC Transform
- (draft-ietf-ipsec-ciph-des-derived-00.txt)
- The ESP DES-CBC Cipher Algorithm With Explicit IV
- (draft-ietf-ipsec-ciph-des-expiv-02.txt)

## IPsec Internet Drafts - Cryptographic Transforms (cont’d)

- The ESP Triple DES Transform
- (draft-ietf-ipsec-ciph-des3-00.txt)
- The ESP 3DES-CBC Algorithm Using an Explicit IV (draft-ietf-ipsec-ciph-3des-expiv-00.txt)
- The ESP DES-XEX3-CBC Transform
- (draft-ietf-ipsec-ciph-desx-00.txt)
- The ESP IDEA-CBC Algorithm Using Explicit IV (draft-ietf-ipsec-ciph-idea-cbc-00.txt)

## IPsec Internet Drafts - Cryptographic Transforms (cont’d)

- The ESP RC5-CBC Algorithm
- (draft-ietf-ipsec-ciph-rc5-cbc-00.txt)
- The NULL Encryption Algorithm and Its Use With Ipsec
-  (draft-ietf-ipsec-ciph-null-00.txt)

## IPsec Internet Drafts -Key Management

- Internet Security Association and Key Management Protocol (ISAKMP)
- (draft-ietf-ipsec-isakmp-09.txt, .ps)
-  The OAKLEY Key Determination Protocol
- (draft-ietf-ipsec-oakley-02.txt)
-  The Internet Key Exchange (IKE)
- (draft-ietf-ipsec-isakmp-oakley-07.txt)

## IPsec Internet Drafts - Key Management (cont’d)

- The Internet IP Security Domain of Interpretation for ISAKMP
- (draft-ietf-ipsec-ipsec-doi-08.txt)
- Inline Keying within the ISAKMP Framework
- (draft-ietf-ipsec-inline-isakmp-01.txt)

## IPsec Internet Drafts -Additional Key Management Modes

- Extended Authentication Within ISAKMP/Oakley
- (draft-ietf-ipsec-isakmp-xauth-01.txt)
- A GSS-API Authentication Mode for ISAKMP/Oakley
- (draft-ietf-ipsec-isakmp-gss-auth-00.txt)
- The ISAKMP Configuration Method
- (draft-ietf-ipsec-isakmp-mode-cfg-02.txt)

## IPsec Internet Drafts - Additional Key Mgmt Modes (cont’d)

- A revised encryption mode for ISAKMP/Oakley
- (draft-ietf-ipsec-revised-enc-mode-01.txt)
- Revised SA negotiation mode for ISAKMP/Oakley
- (draft-ietf-ipsec-isakmp-SA-revised-00.txt)

## IPsec Internet Drafts -Additional Documents

- Implementation of Virtual Private Network (VPNs) with IP Security
- (draft-moskowitz-ipsec-vpn-00.txt)
- Dynamic remote host configuration over IPSEC using DHCP
- (draft-ietf-ipsec-dhcp-00.txt)
- IPSec Policy Data Model
- (draft-ietf-ipsec-policy-model-00.txt)