pgcrypsi

C Crypsi (https://github.com/telkomdev/c-crypsi) PostgreSQL Extension

Motivation/ Why ?

Why not pgcrypto ?. At the time this plugin was created, pgcrypto did not support AES GCM yet. So this plugin is made to fulfill AES GCM encryption needs.

Dependencies

• https://github.com/telkomdev/c-crypsi
• Openssl 1.1.1

pgcrypsi is compatible with each other with the following libraries.

• C/C++ https://github.com/telkomdev/c-crypsi
• Golang https://github.com/telkomdev/go-crypsi
• Python https://github.com/telkomdev/pycrypsi
• C# (.NET) https://github.com/telkomdev/NetCrypsi
• Java/JVM https://github.com/telkomdev/jcrypsi
• NodeJs https://github.com/telkomdev/crypsi
• Javascript (React and Browser) https://github.com/telkomdev/crypsi.js
• MySQL https://github.com/telkomdev/crypsi-mysql-udf

Compatible which means you can directly use existing functions to encrypt and decrypt data. For example, the functions in the Crypsi package for NodeJs below are compatible with the functions in pgcrypsi

pgcrypsi

postgres=# select pgcrypsi_aes_128_gcm_encrypt('abc$#128djdyAgbj', 'this is dark') as res;
                                       res
----------------------------------------------------------------------------------
 817352e89687f1786b6c66939011f9714087a85a87c9eca95ea172067e33d6839235848fed0a32f9
(1 row)

Decrypt the above encrypted data with the crypsi package for Nodejs

const { aesEncryption } = require('crypsi');

const decryptedData = aesEncryption.decryptWithAes128Gcm('abc$#128djdyAgbj', '817352e89687f1786b6c66939011f9714087a85a87c9eca95ea172067e33d6839235848fed0a32f9');
console.log(decryptedData.toString('utf-8')); // result: this is dark

Getting started

Building

Clone

$ git clone https://github.com/telkomdev/pgcrypsi.git

Install PostgreSQL Development server and client

$ sudo apt install libpq-dev
$ sudo apt-get install -y postgresql-server-dev-10

Compile extensions, Create and Copy SHARED Library to /usr/lib/postgresql/10/lib/

$ cc -fPIC -c pgcrypsi.c -I /usr/include/postgresql/10/server/
$ cc -shared -o pgcrypsi.so pgcrypsi.o
$ sudo cp pgcrypsi.so  /usr/lib/postgresql/10/lib/

Notes

To find out what $libdir is referring to, run the following command:

$ pg_config --pkglibdir
/usr/lib/postgresql/10/lib

Install extensions

$ sudo make USE_PGXS=1 install

Install to Database

Login as superuser

$ sudo --login --user postgres
$ psql

Connect to specific Database

$ \c database_name;

Show installed extensions

$ select extname from pg_extension;

Drop extensions

$ DROP EXTENSION IF EXISTS pgcrypsi;

Create extensions

$ CREATE EXTENSION IF NOT EXISTS pgcrypsi;

AES GCM encrypt function

• pgcrypsi_aes_128_gcm_encrypt (AES 128 bit encryption function)
• pgcrypsi_aes_192_gcm_encrypt (AES 192 bit encryption function)
• pgcrypsi_aes_256_gcm_encrypt (AES 256 bit encryption function)

AES GCM decrypt function

• pgcrypsi_aes_128_gcm_decrypt (AES 128 bit decryption function)
• pgcrypsi_aes_192_gcm_decrypt (AES 192 bit decryption function)
• pgcrypsi_aes_256_gcm_decrypt (AES 256 bit decryption function)

Expected key length

• AES 128: key length should be 16 bytes/char
• AES 192: key length should be 24 bytes/char
• AES 256: key length should be 32 bytes/char

Run test

postgres=# \i /home/user/pgcrypsi/test.sql

Test the extensions

Encrypt

postgres=# select pgcrypsi_aes_256_gcm_encrypt('abc$#128djdyAgbjau&YAnmcbagryt5x', 'this is dark') as res;
                                       res
----------------------------------------------------------------------------------
 90fee206d3f41bd92e45e7c876cce4e3f4ed65aeef3cbd05139677bc18d1b393a53848944ef3df05
(1 row)

Decrypt

postgres=# select pgcrypsi_aes_256_gcm_decrypt('abc$#128djdyAgbjau&YAnmcbagryt5x', '90fee206d3f41bd92e45e7c876cce4e3f4ed65aeef3cbd05139677bc18d1b393a53848944ef3df05') as res;
     res
--------------
 this is dark
(1 row)