Laboratory for Reliable Computing Department of Electrical Engineering National Tsing Hua University Hsinchu, Taiwan Security Processor: A Review Chih-Pin Su and Cheng-Wen Wu

Chih-Pin Su 2 Outline  Introduction to Security System  Security service, mechanism and algorithm  Security System Architecture  Conclusion

Chih-Pin Su 3 Reference  “Cryptography and Network Security”, William Stallings  “Network Processors: Architectures, Protocols and, Platforms”, Panos C. Lekkas  “SSL: Foundation for Web Security”, William Stallings, IPJ, Vol.1, No.1  “Security: Adding Protection to the Network via the Network Processor”, Intel Technology journal, Vol.6, Issue 3, P40-49

Chih-Pin Su 4 Security Requirement  Access Control – unauthorized users are kept out  Authentication – Assurance of identity of person or originator of data  Confidentiality – Protection from disclosure to unauthorized person  Integrity – Maintain data consistency, protection against unauthorized data alternation  Non-repudiation – Originator of communications can not deny it later  Availability – Legitimate users have access when they need it

Chih-Pin Su 5 Security Threat  Information disclosure  Integrity violation  Masquerading  Denial of service  Illegitimate use  Generic threat: backdoors, Trojan horses, insider attacks

Chih-Pin Su 6 Security Service  From Open System Interconnection (OSI) definition  Access Control  Authentication  Confidentiality  Integrity  Non-repudiation ITU-TT, X.800: Security Service of OSI

Chih-Pin Su 7 Security Mechanisms  Three basic building blocks are used  Encryption is used to provide confidentiality, can provide authentication and integrity protection  Digital signatures are used to provide authentication, integrity protection, and non- repudiation  Checksums/hash algorithms are used to provide integrity, can provide authentication  Multiple security mechanisms are combined to provide a security service

Chih-Pin Su 8 Service, Mechanism, Algorithm  Services are built from Mechanisms  Mechanisms are implemented using algorithms SSL SignaturesEncryptionHashing RSADSAAESSHA1MD5DES Service (in security Protocol) Mechanism Algorithm

Chih-Pin Su 9 Conventional Encryption  Using a shared key  Problem of transferring a large message in secret reduced to transferring a small key in secret  Also called Private- or Symmetric-Key Encryption  Block cipher and stream cipher  Cryptographic mode – ECB, CBC, CFB, OFB mode

Chih-Pin Su 10 Public-Key Encryption  Uses matched public/private key pairs  Asymmetric-key encryption  Anyone can encrypt with the public key, only one person can decrypt with the private key

Chih-Pin Su 11 Key Agreement  Allow two parties to agree on a shared key  Provides part of the required secured channel for exchanging a conventional encryption key

Chih-Pin Su 12 Hash Function  Create a unique “fingerprint” for a message  Anyone can alter the message and create a new hash value

Chih-Pin Su 13 MAC  Message Authentication Code, adds a password/key to a hash  Only password/key holder can generate the MAC  HMAC-SHA, HMAC-MD5

Chih-Pin Su 14 Digital Signatures  Combines a hash with a digital signature algorithm

Chih-Pin Su 15 Message/Data Encryption  Combines symmetric- and asymmetric-key encryption

Chih-Pin Su 16 Security Protocol Layers

Chih-Pin Su 17 SSL  Secure Socket Layer – TCP/IP socket encryption  Usually authenticates server using digital signature  Can authenticate client but never used  Confidentiality protection via encryption  Integrity protection via MAC’s  Provides end-to-end protection of communication sessions

Chih-Pin Su 18 SSL Handshake  Negotiate the cipher suite  Established a shared session key  Authenticate the server (opt.)  Authenticate the client (opt.)  Authenticate previously exchange data

Chih-Pin Su 19 SSL Data Transfer

Chih-Pin Su 20 Popular Security Algorithm  Hash algorithm: HMAC-MD5, HMAC-SHA1, RIPEMD-128/160  Encryption algorithm: DES/3DES, AES, ARC4  Public Key algorithm: RSA, DSA sign and verify, ECC

Chih-Pin Su 21 Key Management  Key management is the hardest part of cryptography  Two classes of keys  Short-term session keys  Generated automatically and invisibly  Used for one message or session and discarded  Long-term keys  Generated explicitly by the user  Long-term keys are used for two purposes  Authentication (including access control, integrity, and non- repudiation)  Confidentiality (encryption)  Establish session keys  Protect stored data

Chih-Pin Su 22 Key Management Problem  Key certification  Key distribution  Obtaining someone else’s public key  Distributing your own public key  Establishing a shared key with another party  Confidentiality: Is it really known only to the other party?  Authentication: is it really shared with the intended party?  Key storage  Secure storage of keys  Revocation  Revoking published key  Determining whether the published key is still valid

Chih-Pin Su 23 Key Distribution  A Certification Authority (CA) solve the problem Intercept!

Chih-Pin Su 24 Functional Block of Network Processing Host Processing Switch Fabric chip PHY layer chip Queuing Compression Encryption Modification Lookup/classification Parsing/Framing Slow Path Processing Transmission medium

Chih-Pin Su 25 Security System Architecture (1)  Look-aside architecture Switch Fabric Network Processor PHY/MAC Security Coprocessor Host CPU subsystem SDRAM Session State memory Incoming trafficOutgoing traffic

Chih-Pin Su 26 Security System Architecture (2)  Flow-through architecture Switch Fabric Network Processor PHY/MAC Security Coprocessor Host CPU subsystem SDRAM Session State memory Incoming trafficOutgoing traffic

Chih-Pin Su 27 SafeNet 1741  IPSec accelerator

Chih-Pin Su 28 Motorola MPC8272  PowerQUICC with integrated security engine

Chih-Pin Su 29 Intel IXP2850

Chih-Pin Su 30 Crypto-Engine in IXP2850

Chih-Pin Su 31 Conclusion  Basic concept of a security system is introduced  System architecture of security processor  Look-aside architecture  Flow-through architecture  Integrated architecture