Establishing a connection to a PostgreSQL database where data is encrypted using the AES standard requires a few understandings since PostgreSQL does not support full database-level AES encryption out of the box. However, there are ways to secure walls and alternatives to dealing with AES encryption using PostgreSQL.
Encryption in Rest: In PostgreSQL, it is possible to use file-level encryption when storing data in the database several times. This is done by having the whole disk or a filesystem encrypted using the Advanced Encryption Standard (AES) algorithm, for example, by using LUKS in Linux. This method secures the information contained in the disk but it is not disk encrypted database specific. When it comes to encrypting an entire database, one can easily use tools like pgcrypto, which provides a function that encrypts or decrypts a particular column with AES.
Incorporating pgcrypto in Column Level Encryption: The pgcrypto extension allows the storage of certain selected pieces of information in coded or encrypted form at the level of the column. For instance:
CREATE EXTENSION pgcrypto;
INSERT INTO my_table (encrypted_column)
VALUES (pgp_sym_encrypt('my data', 'my_secure_key', 'aes'));
To decrypt:
SELECT pgp_sym_decrypt(encrypted_column::bytea, 'my_secure_key') FROM my_table;
This approach gives you well-defined control over encryption.
Secured Network Connections and Key Management: Key management cannot be overemphasized. Do not keep the keys in the database. Instead, you should put them in AWS KMS, Azure Key Vault, HashiCorp Vault, or other similar services that offer the best security for key storage and handling. Keys should be made available to only a few applications with no external access to keys except through the appropriate environmental variables or secured tokens.
Secure Datalinks – SSL/TLS for Data in Transit: It is also important to encrypt any data being sent over the wire, for example, using SSL/TLS. PostgreSQL provides support for SSL connections, and one can enable SSL in the PostgreSQL configuration file to make all connections secure.
In conclusion, AEAD encryption, which is natively supported by PostgreSQL, cannot be used for whole database encryption because it does not provide such features. However, pgcrypto can be used for column-level encryption and protecting sensitive information. For safe operations, a KMS should be utilized for key management encryption keys and SSL for data in-use protection.