Encryption and Data Security

1. Encryption and Data Security Jungles, Towers, Monkeys, Locks and Keys.

2. 4 דרישות לקיום תקשורת מאובטחת: Confidentiality - סודיות Integrity - שלמות Interception Modification Is my communication private? Has my communication been altered? Authentication - הזדהות Non-repudiation - מניעת התכחשות ? Claims NotSent NotReceived Fabrication Who am I dealing with? Who sent/received it and when?

3. Agenda • What are EC Security Threats and Issues • Web server and Database Security • Crypto-Basics • Network Encryption • SSL/PCT

4. Agenda (2) • Main concepts :Physical vs. Logical protectionsSymmetric vs. Public Key encryptionPrivacy, Integrity, Repudiation, • Hash, Digital signature, Certification • Security vs. Privacy as public interest concernsDES, SSL

5. Security - The Business Challenge Who’s the bad guy? Competitors, foreign governments, network hackers, disgruntled ex-employees, news and media, unauthorized customers, employees, etc? How do I protect my information from the bad guys, without making employees and authorized users less productive? Outsiders 20% Insiders 80% How can I administer security consistently, reliably, and cost effectively across all of my distributed information resources ? Studies show 80% of real security problems are caused by authorized users

6. Security Threats in Electronic Commerce • Client/server security • ensuring that only the right people are accessing the network resources or content on Web servers. • This includes: password protection, encrypted smart cards, biometrics, and firewalls. • Data and transaction security • ensuring the privacy and confidentiality in electronic messages and data packets. • This includes: data encryption using various cryptographic methods.

7. Today’s Client-Server Environment • Introduces new network security vulnerabilities • password/datastream snooping • datastream modification • Potential user population becomes much bigger • User and host identification more difficult • Physical security no longer enough Server EnterpriseNetwork Host-basedSystem Clients

8. TEMPEST, “Echelon”, “Carnivore” • Transient Electromagnetic Pulse Emanation Standard • FBI’s “Carnivore”

9. Menwith Hill in the UK: Alleged to be part of Echelon

10. אמצעים פיזיים לשמירה על דרישות האבטחה: סודיות: מעטפה חתומה שלמות: חותמת עדות הזדהות: תעודת זהות, דרכון מניעת התכחשות:חתימה + תאריך My Signature & Date

11. User Identification & Authentication • choices for user authentication • Using passwords • Using Biometric devices or tokens • Single Sign-On for host-based systems • Single Sign-On Integration for network-based distributed security frameworks

12. Access Controls • Object privileges implements ‘need to know’ security • Views extend object security to row, column level based on content or context • Stored procedures, packages and functions support ‘execute only’ privileges on well-formed transactions • Roles provide privilege management

13. Auditing & Accountability • Audit Flexibility and Granularity • Audit objects, users, operations, privileges... • Securely Analyze Audit Information using SQL • Database triggers enable context-sensitive auditing Hold Users Responsible by...

14. Crypto Basics

15. The Internet And Security • Internet is open • Anyone can listen, modify,or repudiate transactions • Security needs are verydifferent than traditional LANs • No a priori information about users • Large scale - millions versus thousands • Completely decentralizedsecurity infrastructure • Executable content

16. Users’ Security Needs • Communicate privately • Transmit confidential, personal information • Verify identity of other parties • Authenticate Web servers, clients • Control access to information, resources • Distribute private, paid-for information • Create virtual private networks • Conduct secure transactions • Assure safety of order, payment information • Ensure software authenticity • Download trusted code from Internet

17. Need for Secure Communications • Secure Web Channels needs to provide access to servers with: • Privacy: packets can’t be snooped • Integrity: packets can’t be altered • Authentication: no TCP/DNS spoofing • Certification • Blinding • Key Exchange STANDARDS?

18. The basis of cryptography Plain text Cipher text Blah Blah Blah Blah Blah Blah Blah Blah Blah Blah Blah Blah Blah Blah Blah Blah Blah Blah Blah Blah Blah Blah Blah Blah xdffhliouse345 fjged09e5fjsks qwfnxpdifuw0 awdbczoksrya aaksjhaswe4u fdnaweaa2wfs awrkjsfya38yf kpo80sdw304v Key Encryption Decryption The key uses a mathematical algorithm to transform plaintext into ciphertext and back again

19. Symmetric Key Encryption Plain-text input Plain-text output Cipher-text “The quick brown fox jumps over the lazy dog” “The quick brown fox jumps over the lazy dog” “AxCv;5bmEseTfid3)fGsmWe#4^,sdgfMwir3:dkJeTsY8R\s@!q3%” Encryption Decryption Same key (shared secret)

20. Symmetric encryption • ROT13 - no better than decoder rings, Ceasar’s code, AT-BaSh • Application embedded (see accessdata.com) • DES: US Govmnt. standard. 16 reshuffles of 64 bit data chunks. Relatively short (56 bit) key. Efficient! Can be broken, with long hours use of brute force. No practical attack published yet. Key choice is a vulnerability.

21. Symmetric encryption (2) • Triple DES (3DES) Applees DES three times. Can get encryption with up to 168 or 112 bit key. Not restricted by patents. • IDEA (International Data Encryption Algorithm) shuffles 64 bits at a time, like DES. 128 bit key, which is long enough to resist brute force keyspace search.

22. public private Public Key Encryption Clear-text input Clear-text output Cipher-text “The quick brown fox jumps over the lazy dog” “The quick brown fox jumps over the lazy dog” “Py75c%bn&*)9|fDe^bDFaq#xzjFr@g5=&nmdFg$5knvMd’rkvegMs” Encryption Decryption Different keys Recipient’s public key Recipient’s private key

23. public private SMART CARD private 123 89 3486 M Public Key Pairs Public and private keys are always generated as amatchedpair Keys are mathematically related but it is computationally infeasible to deduce a private key from its public key Private keys are kept secret - preferably by being stored in a tamper-resistant chip Public keys are just that - public!

24. Key Management • Key Management is THE problem/opportunity • Public and private keys are always generated as a pair at the user’s machine • Public key can be openly shared • Private key is always kept private(it never leaves the machine where it was generated)

25. Key Pair Use • Recipient’s public key is used to send a randomly chosen communication key • Sender’s private signing key is used in digital signature operations • Recipient verifies signature using sender’s public signing key

26. Why Use PublicKey Authentication • Better security than passwords • Better scalability than passwords • No need to distributepassword databases • Builds to emerging technologies • SmartCards • Crypto accelerators

27. Why Use PublicKey Authentication • Key distribution: how keys are created and moved to where they will be used. • Key revocation: how compromised keys are recovered or at least invalidated. CONTAINMENT: dealing with the outcome of a breach in security.

28. Why Use PublicKey Authentication • The cost of key distribution plus the cost of key revocation is a constant. • As a result, secret (symmetric) key systems have high distribution costs but low revocation costs. Public key systems have low distribution costs and high revocation costs.

29. Secure Communication • Symmetric encryption for data • Public key too slow for bulk data encryption • Export restrictions don’t allow bulk encryption using public key • Uses key-exchange key pair • Public key exchange key of recipient is used to privately share the symmetric key

30. public private Secure Communication (1)Sender generates a random symmetric “session” key A03DB982402C23F Encryption Decryption (3)Recipient uses its private key to decrypt session key (2)Sender encrypts session key using recipient’s public key

31. Digital Signature • Used like a handwritten signature • Verifies the identity of the signer • Guarantees the document has not been modified since signed • Basis for non-repudiation • Uses a separate signature key pair • Document hash encrypted with signer’s private signature key

32. מה זה HASH ? דוגמא של חישוב ספרת ביקורת במספר ת.ז • מספר תעודת הזהות מורכב מ- 8 ספרות וספרת ביקורת. • אופן חישוב ספרת הביקורת היא פעולת HASHעל מספר ת.ז. • אופן חישוב ספרת הביקורת: 2 5 7 4 5 7 3 0 - המספר ללא ספרת ביקורת | | | | | | | | * 2 1 2 1 2 1 2 1- פונקציית ה- Hash 4 5 5 4 1 7 6 0 • מחשבים את סכום הספרות => 32 • התוצאה הסופית של פונקצית ה- HASHהיא ספרת ההשלמה למספר עשרות שלם (בדוגמא הנ”ל ל- 40), מהווה את ספרת הביקורת - כלומר 8. • לפיכך, מס’ תעודת הזהות השלם, במקרה הנוכחי – 03754752-8 * אם מתקבלת מכפלה גדולה מ- 9, מחשבים את סכום הספרות, למשל 14=2*7, ולכן הספרה שנרשמת היא 5=1+4

33. Electronic Data Electronic Data Signing(Encrypt) Function Hash Result Hash Function Digital Signature Signed Data Private of A חתימה דיגיטלית של מידע Only Private Key holder can sign

34. Electronic Data Verify(Decrypt) Function Hash Result Hash Result Hash Function Digital Signature Valid compare Yes / No ? Signed Data Public of A אימות של חתימה דיגיטלית המקבל, יכול לבצע השוואה בין תוצאות ה- HASHע”מ לוודא כי המידע שנשלח אליו לא שונה בדרך Anyone can verify

35. Originaldoc Digital Signature Priv key Originaldoc One-way hash Signed document SHA

36. Certificates • Digitally signed document • Associates identity with public key(s) • Signed by a “trusted” certifying authority • Identity proved by ability to encryptusing associated private key

37. Name: “Jane Doe” Key-Exchange Key: public Signature Key: public Serial #: 29483756 private Other Data: 10236283025273 Expires: 6/18/98 Signed: CA’s Signature Certificates The authenticity of the certificate is guaranteed by the digital signature generated using the CA’s private key Certificate binds a name to public key(s) Credential expiration

38. Certificates • Certifying authority • Binds name to certificate • Can be multiple CAs in a hierarchy • Certification can be delegated... • Trust can form a “Web” • More than one party can certify an entity

39. OriginalDocument MD5 Pub Name: “Jane Doe” Key-Exchange Key: public Signature Key: public Serial #: 29483756 Card Authenticator: 10236283 Expires: 6/18/96 Signed: CA’s Signature Name: “Jane Doe” Key-Exchange Key: public Signature Key: public Serial #: 29483756 Card Authenticator: 10236283 Expires: 6/18/96 Signed: CA’s Signature Establishing Trust (1) Verify digital signatureon document Hash 1 COMPARE? Hash 2 SignedDocument This document is signed by Barbara (2) Verify the digital signatureon Barbara’s affidavit by checking it against Steve’s public key(found in Steve’s affidavit) This is Barbara’s affidavit, which is signed by Steve (3) Verify the digital signatureon Steve’s affidavit by checking it against the trusted root public key This is Steve’s affidavit, which is signed bythe trusted root The trusted root’s public key is hardcoded in the software or a self-signed certificate is in the registry

40. Encryptionon the Network

41. Network Encryption (VPN) • Network Encryption provides • privacy & confidentiality for all data, commands, passwords, etc. passing over the network • integrity sealing / tamper proofing for all data • Encryption keys are generated and managed automatically - on a per-session basis NETWORK

42. MD5 SECURE MESSAGE DIGEST Network Encryption Protocols Integrity Algorithms Confidentiality Algorithms • Algorithm choice negotiated at connection time 128-bit, 56-bit, and 40-bit RC4 DES and DES40 Fortezza SHA Fortezza SHA Secure Automatic Key Management using Diffie-Hellman seed=ABCD Key Generator Key Generator seed= 5678

43. Secure Connection onthe World Wide WebSSL/PCT protocol information

44. Client Server Application data Application data SSL 3.0 Handshake ClientHello ServerHello Certificate* CertificateRequest* ServerKeyExchange ClientKeyExchange Certificate* CertificateVerify* Changecipherspec Finished Changecipherspec Finished * Indicates optional or situational-dependentmessages that are not always sent

45. Secure Connection Features • Secures socket connection • Quick reconnect • Provides encryption andmessage authentication • Public-key-based key exchange • Authenticates serverand (optionally) client

46. Privacy vs. Accountability • Small towns are wonderful places, because you know everybody. • Small towns are awful places, because everyone knows you.

47. Privacy vs. Accountability • Liberty vs. Civil order Benjamin Franklin: Those who would trade Liberty for Security deserve neither. Thomas Paine: The price of Freedom is eternal Vigilance.

48. Privacy vs. Accountability • Liberty vs. Civil order Esther Dyson: Encryption is a powerful defensive weapon for free people. It offers a technical guarantee of pivacy regardless of who is running the government. It’s hard to think of a more powerful, less dangerous tool for liberty.

49. Privacy vs. Accountability • Liberty vs. Civil order Simson Garfinkel: Privacy could be the crowbar that finally splits the classes apart for good. We already have the financially rich and financially poor, and the information-rich and information-poor. But we may soon add the privacy-rich and privacy-poor. And that could be the biggest threat to democracy yet.

50. PGP, created by Phil Zimmermann, is a good example of public key cryptography It gives you privacy by allowing you to encrypt your files and email so that nobody can read them except the people you choose PGP allows you to create a digital signature on your files and email