Crypto

Use the Crypto commands to encode and decode ASCII text strings to and from Base64, as well as obtain CRC16, HMAC, and MD5 values for specified strings.

Compute the Base64 of a specified string.

Syntax

Crypto.Base64Encode('value', [pad])

Arguments

value : The value, enclosed within quotes, to encode to Base64.

pad : (Optional) Replace with true | false. If true, output is padded with '=' signs. The default is true.

Examples

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print (Crypto.Base64Encode('Hello there'))

Debug Output

SGVsbG8gdGhlcmU=
Copy 
print (Crypto.Base64Encode('Hello there',false))

Debug Output

SGVsbG8gdGhlcmU

Convert the Base64 of a specified value to a string.

Syntax

Crypto.Base64Decode('value')

Arguments

value : The value, enclosed within quotes, to decode from Base64.

Example

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print (Crypto.Base64Decode('SGVsbG8gdGhlcmU='))

Debug Output

Hello there

Compute the CRC16 of a specified value.

Syntax

Crypto.CRC16Compute( 'value' )

Arguments

value : The value, enclosed within quotes, used to generate the CRC16.

Example

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Crypto.CRC16Compute('Hello there')

Table with values for supported ciphers.

Syntax

Crypto.Cipher.cipher

Arguments

AES_128_CBC : aes_128_cbc

AES_128_ECB : aes_128_ecb

AES_256_CBC : aes_256_cbc

AES_256_ECB : aes_256_ecb

Note: While there are many available ciphers in OpenSSL, these are specifically supported in Q-SYS.

Example

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Crypto.Cipher.AES_128_CBC

Block-based decryption. Will raise error on failure.

Syntax

Crypto.Decrypt ( cipher, key, iv, cipher_text )

Arguments

Note: Crypto.Decrypt requires that the key and iv match the length of the cipher

cipher : <string> - value from Crypto.Ciphers table

key : <string>

iv : <string> (can be empty)

cipher_text : <string>

Example

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decrypted_iv = Crypto.Decrypt(Crypto.Cipher.AES_128_ECB,key,nil,encrypted_iv)

Compute the message digest of specified data using a specified hashing algorithm.

Syntax

Crypto.Digest('algorithm', 'data')

Arguments

algorithm : Replace with md5 | sha1 | sha256 | sha512 , enclosed within quotes.

data : The data for which to compute the message authentication code, enclosed within quotes.

Example

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Crypto.Digest('md5','Hello there')

Block-based encryption. Will raise error on failure.

Syntax

Crypto.Encrypt ( cipher, key, iv, message, padding )

Arguments

Note: Crypto.Encrypt requires that the key and iv match the length of the cipher

cipher : <string> - value from Crypto.Ciphers table

key : <string>

iv : <string> (can be empty)

message : <string>

padding : <bool> default = true, if false then message must be multiple of block size

Example

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Crypto.Encrypt( Crypto.Cipher.AES_128_ECB, key, nil, iv, false )

Create a series of random bytes.

Syntax

Crypto.GetRandomBytes(count)

Arguments

count : <number>

Example

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Crypto.GetRandomBytes(13)

Table with values for supported hash functions. Not all hashes are necessarily supported in every function.

Syntax

Crypto.Hash.hash_function_type

Arguments

hash_function_type : Replace with MD5 | SHA1 | SHA256 | SHA512.

Example

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Crypto.Hash.MD5

Compute the message authentication code of specified data using a specified hashing algorithm and key.

Syntax

Crypto.HMAC('algorithm', 'key', 'data')

Arguments

algorithm : Replace with md5 | sha1 | sha256 | sha512 , enclosed within quotes.

key : The secret key to use for computing the message authentication code, enclosed within quotes.

data : The data for which to compute the message authentication code, enclosed within quotes.

Example

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Crypto.HMAC('md5','123456789','Hello there')

Compute the MD5 hash of a specified value.

Syntax

Crypto.MD5Compute( 'value' )

Arguments

value : The value for which to compute the MD5 hash.

Example

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print (Crypto.MD5Compute('Hello there'))

Debug Output

e8ea7a8d1e93e8764a84a0f3df4644de

Implementation of Password-Based Key Derivation Function 2. Will raise error on failure.

Syntax

Crypto.PBKDF2( 'value' )

Arguments

password : <string>

salt : <string>

iterations : <number>

keylen : <number>

digest : <string> - "sha1", "sha256", "sha512"

Example

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salt = string.char(0xaa, 0xef, 0x2d, 0x3f, 0x4d, 0x77, 0xac, 0x66, 0xe9, 0xc5, 0xa6, 0xc3, 0xd8, 0xf9, 0x21, 0xd1)
password = "p@$Sw0rD~1"
key = Crypto.PBKDF2(password, salt, 50000, 32, Crypto.Hash.SHA256)

print(bitstring.hexdump(key))

Debug Output

2023-06-20T19:13:35.110	00000000: 52 c5 ef a1 6e 70 22 85   90 51 b1 de c2 8b c6 5d     R...np"..Q.....]
00000010: 96 96 a3 00 5d 0f 97 e5   06 c4 28 43 bc 3b db c0     ....].....(C.;..