drill-crypto-docs.md

Drill Crypto Functions

This library contains a collection of cryptography-related functions for Apache Drill. It generally mirrors the crypto functions in MySQL. The package includes:

• aes_encrypt()/ aes_decrypt(): implement encryption and decryption of data using the official AES (Advanced Encryption Standard) algorithm, previously known as “Rijndael.” AES_ENCRYPT() encrypts the string str using the key string key_str and returns a binary string containing the encrypted output. AES_DECRYPT() decrypts the encrypted string crypt_str using the key string key_str and returns the original cleartext string. If either function argument is NULL, the function returns NULL.

> SELECT aes_encrypt( 'encrypted_text', 'my_secret_key' ) AS aes FROM (VALUES(1));
+---------------------------+
|            aes            |
+---------------------------+
| JkcBUNAn8ByKWCcVmNrKMA==  |
+---------------------------+

 > SELECT aes_encrypt( 'encrypted_text', 'my_secret_key' ) AS encrypted,
 aes_decrypt(aes_encrypt( 'encrypted_text', 'my_secret_key' ),'my_secret_key') AS decrypted 
 FROM (VALUES(1));
+---------------------------+-----------------+
|         encrypted         |    decrypted    |
+---------------------------+-----------------+
| JkcBUNAn8ByKWCcVmNrKMA==  | encrypted_text  |
+---------------------------+-----------------+

• md2(<text>): Returns the md2 hash of the text. (https://en.wikipedia.org/wiki/MD2_(cryptography)) Usage:

> select md2( 'testing' ) from (values(1));
+-----------------------------------+
|              EXPR$0               |
+-----------------------------------+
| fc134df10d6ecafceb5c75861d01b41f  |
+-----------------------------------+

• md5(<text>): Returns the md5 hash of the text. (https://en.wikipedia.org/wiki/MD5) Usage:

> select md5( 'testing' ) from (VALUES(1));
+-----------------------------------+
|              EXPR$0               |
+-----------------------------------+
| ae2b1fca515949e5d54fb22b8ed95575  |
+-----------------------------------+

• sha(<text>) / sha1(<text>): Calculates an SHA-1 160-bit checksum for the string, as described in RFC 3174 (Secure Hash Algorithm). (https://en.wikipedia.org/wiki/SHA-1) The value is returned as a string of 40 hexadecimal digits, or NULL if the argument was NULL. Note that sha() and sha1() are aliases for the same function.

> select sha1( 'testing' ) from (VALUES(1));
+-------------------------------------------+
|                  EXPR$0                   |
+-------------------------------------------+
| dc724af18fbdd4e59189f5fe768a5f8311527050  |
+-------------------------------------------+

• sha2(<text>) / sha256(<text>): Calculates an SHA-2 256-bit checksum for the string. (https://en.wikipedia.org/wiki/SHA-2) The value is returned as a string of hexadecimal digits, or NULL if the argument was NULL. Note that sha2() and sha256() are aliases for the same function.

> select sha2( 'testing' ) from (VALUES(1));
+-------------------------------------------------------------------+
|                              EXPR$0                               |
+-------------------------------------------------------------------+
| cf80cd8aed482d5d1527d7dc72fceff84e6326592848447d2dc0b0e87dfc9a90  |
+-------------------------------------------------------------------+

Additionally, there are also sha384(<text>) and sha512(<text>) functions which return SHA-2 hashes with 384 and 512 bit checksums.