How Do I Encrypt and Decrypt Data? (Magic xpa 3.x)

You can use the Magic xpa Cipher() and DeCipher() functions to specifically encrypt and decrypt a BLOB of data. These support specific encryption algorithms, so you can decipher data coming from other applications. The supported algorithms include both symmetric algorithms like Blowfish and asymmetric algorithms such as RSA.

Symmetric algorithms make use of the same key for encrypting and decrypting data. Other algorithms are asymmetric, and you need a key pair, one to encrypt and one to decrypt.

Using Cipher()

The syntax for Cipher() is:

Cipher(Cipher ID, Buffer, Key [, Mode, IV])

Where:

• Cipher ID is a number representing which encrypting algorithm to use. In our example we used 1, which is Blowfish (See the Supported encryption methods section below).

• Buffer is the BLOB that contains the data to encrypt.

• Key is a BLOB containing the key. The required key length depends on which algorithm you are using. In our example our key is the word ‘SECRET’.

• Mode is an optional parameter specifying which mode to use. The allowable modes depend on the encrypting algorithm.

• IV is a BLOB containing an initialization vector. This parameter is also optional.

Cipher() returns a BLOB, which contains the encrypted text.

Using Decipher()

The syntax for Decipher() is identical to that of Cipher():

Decipher(Cipher ID, Buffer, Key [, Mode, IV])

Where:

• Cipher ID is a number representing which encrypting algorithm to use. In our example we used 1, which is Blowfish (See the Supported encryption methods section below).

• Buffer is the BLOB that contains the data to encrypt.

• Key is a BLOB containing the key. The required key length depends on which algorithm you are using. In our example our key is the word ‘SECRET’.

• Mode is an optional parameter specifying which mode to use. The allowable modes depend on the encrypting algorithm.

• IV is a BLOB containing an initialization vector. This parameter is also optional.

Decipher() returns a BLOB, which contains the decrypted text.

Supported encryption methods

Algorithm Name	Cipher Code	Supported Modes and IV (Length in bytes)	Key Length (in bytes)	Symmetry
BLOWFISH	1	ECB - NA CBC - 8 CFB - 8 OFB - 8	Supported: 1 – 56 Recommended: 16	Symmetric
CAST	2	ECB - NA CBC - 8 CFB - 8 OFB - 8	Supported: 5 – 16 Recommended: 8	Symmetric
DES	3	ECB - NA CBC - 8 CFB - 8 OFB - 8	Supported: 8 Recommended: 8	Symmetric
RC2	5	ECB - NA CBC - 8 CFB - 8 OFB - 8	Supported: 5 – 16 Recommended: 8	Symmetric
RC4	6	Not Applicable	Supported: 1 – NR Recommended: 16	Symmetric
RC5	7	ECB - NA CBC - 8 CFB - 8 OFB - 8	Supported: 1 – 255 Recommended: 16	Symmetric
DES3	8	ECB3 - NA CBC3 - 8	Supported: 16 and 24 Recommended: 24	Symmetric
RSA	9	Not Applicable	Supported: 48 – 2048 Recommended: 128	Asymmetric
AES	10	ECB - NA CBC - 8 CFB - 8 OFB - 8	Supported: 16, 24, 32 Recommended: 16	Symmetric

See also

The Online and Rich Client Samples projects (program SE01 and RSE01)