# 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.
```sql
> 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:
```sql
> 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:
```sql
> 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.
```sql
> 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.
```sql
> 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.
Task
Major