1 / 15

Using Crypto in RDBMS

Learn about the importance of using cryptographic techniques in relational databases to protect data from theft and modification. Explore different crypto primitives such as hash, cipher, digital signature, and MAC. Discover strategies for protecting data in various scenarios like encrypting the database itself, encrypting specific parts of the data, and ensuring secure replication and backups. Understand the implementation of crypto in PostgreSQL using pgcrypto and explore advanced techniques like property-preserving encryption, homomorphic encryption, and format-preserving encryption.

moonc
Download Presentation

Using Crypto in RDBMS

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Using Crypto in RDBMS PgDay.ru – 2016 Saint-Petersburg July 7-8, 2016 Dmitry Belyavskiy, Technical Centre of Internet

  2. You have data! 2 ways of attack – 2 ways of protection: • The attacker may steal data • The attacker may modify data You want to protect data Rule 1: Do not invent your own crypto!

  3. Crypto ops: Classification Main crypto primitives: • Hash (message digest) • Cipher • Digital signature • MAC • Helper algorithms: KDF, PRF… Datastealing Data modifying

  4. Hash • Any data => fixed-length data • Non-revertible • Hard to find pre-image • Hard to find collision • Algorithms: MD5, SHA1, SHA2, SHA3… • Length: 128-512 bits

  5. Ciphers • Any data => Any data • Revertible • Algorithms: AES, Camellia, 3DES, ChaCha… • Many modes: • ECB: the same input => the same output • All other: IV to make result different Source: https://blog.filippo.io/the-ecb-penguin/

  6. Passwords: Hash vs Cipher Hash • Same input => same output • Rainbow tables • Need extra data to make values unique • HMAC = HASH (salt, data). • Salt to be stored in DB • Bcrypt/scrypt Cipher • Where is my key? • Password length is known (padding helps) => Dictionary attack

  7. Digital signature • Any data => (hash) => (private key) => signature • Algorithms: ECDSA, RSA, Ed25519… • Data is untouched • Signature may be stored aside • Signature keys expire from time to time

  8. What do we protect? • Threat model • Protect traffic to database? Enable TLS! • Protect data in DB? Think about encrypted FS. • PostgreSQL: patches to encipher the DB itself. • Long ago: http://archives.postgresql.org/pgsql-hackers/2011-10/msg01213.php • New: http://www.cybertec.at/2016/06/postgresql-instance-level-encryption/ • Some parts of data? • Where is the key? • No search. • No ORDER BY. At least now… • Encryption for the DB owner – S/MIME, CMS… • Replication && backups! • http://evol-monkey.blogspot.ru/2015/10/postgresql-94-streaming-replication.html

  9. Crypto implementation in PostgreSQL • Pgcryptohttps://www.postgresql.org/docs/current/static/pgcrypto.html • Can use OpenSSL or not • PGP operations • crypt/gen_salt for storing passwords • Low-level operations • Some low-level crypto primitives (MD5, SHA1) are built-in.

  10. To be done • Property-preserving encryption • Homomorphic encryption • Format-preserving encryption

  11. Property-preserving encryption A B => Encrypt(A)  Encrypt(B) • Description: • https://css.csail.mit.edu/cryptdb/ • http://research.microsoft.com/en-us/projects/cipherbase/ • Analysis: • http://bristolcrypto.blogspot.co.at/2015/10/inference-attacks-on-property.html • http://outsourcedbits.org/2015/09/07/attacking-encrypted-database-systems/

  12. Homomorphic encryption Encrypt (AVG(A, B, C…)) = AVG(Encrypt(A), Encrypt(B), Encrypt(C)…) • Privacy to rule them all! • http://research.microsoft.com/apps/pubs/default.aspx?id=148825 • http://research.microsoft.com/apps/pubs/default.aspx?id=258435 • http://research.microsoft.com/pubs/258435/ManualHEv2.pdf

  13. Format-preserving encryption Is the phone, SSN, or credit card encrypted or not? No changes to database schema! • NIST:Recommendation for Block Cipher Modes of Operation: Methods for Format-Preserving Encryptionhttp://nvlpubs.nist.gov/nistpubs/SpecialPublications/NIST.SP.800-38G.pdfhttps://app.box.com/shared/static/tvc6cgfyswdocghv3cnffu32w3jndiu9.pdf

  14. Last but not least • PCI-DSS Compliance • The Payment Card Industry Data Security Standard (PCI DSS) is a proprietary information security standard for organizations that handle branded credit cards from the major card schemes https://wiki.postgresql.org/images/2/24/Achieving_PCI_Compliace_PgConfNYC2014.pdf

  15. Questions? beldmit@tcinet.ru

More Related