DecryptStandard (Function) In french: DécrypteStandard
 Warning
From version 24, UncryptStandard is kept for backward compatibility. This function is replaced by DecryptStandard.
Decrypts a message that was encrypted with a standard encryption algorithm. Unlike Encrypt and Decrypt, EncryptStandard and DecryptStandard use the standard encryption algorithms that allow you to exchange encrypted messages between different runtime platforms (Windows, Linux, Android, Java, iOS, PHP, etc.) and/or with external tools.
// Encrypt a character string by using the AES algorithm
sMessage is Buffer = "Message to encrypt"
sPassword is ANSI string = "password"
bufKey is Buffer = HashString(HA_MD5_128, sPassword)
bufEncrypt is Buffer = EncryptStandard(sMessage, bufKey, cryptAES128)
// Decryption
bufResult is Buffer = DecryptStandard(bufEncrypt, bufKey, cryptAES128)
Info(bufResult)
Syntax
<Result> = DecryptStandard(<Encrypted message> , <Key> [, <Algorithm> [, <Operation mode> [, <Padding>]]])
<Result>: Binary buffer - Result of decryption for the specified message,
- Empty string ("") if an error occurred. To get more details on the error, use ErrorInfo.
<Encrypted message>: Binary buffer Message to decrypt. This message can be the encryption result obtained during the call to EncryptStandard.This buffer must include two sections: - The initialization vector (or IV) used to encrypt data.
- The encrypted data.
If the message was encrypted: - by EncryptStandard, this parameter must correspond to the value returned by the function.
- by an external tool, the buffer must be built by concatenating the encrypted data to initialization vector used.
Remark: if the specified operation mode is cryptECB, no initialization vector was used to encrypt the message and in this case, the parameter must directly correspond to the encrypted data. <Key>: Buffer Key with which the data was encrypted. This key must be identical to the one supplied when encrypting the message. <Algorithm>: Optional Integer constant Encryption algorithm used. This parameter must correspond to the algorithm used to encrypt the message. | | | crypt3DES | Triple Data Encryption Standard. - Size of key: 192 bits.
- Size of blocks: 64-bit.
- Size of initialization vector (IV): 64-bit.
| cryptAES128
(Default value) | Advanced Encryption Standard. - Size of key: 128 bits.
- Size of blocks: 128 bits.
- Size of initialization vector (IV): 128 bits.
| | cryptAES256 | Advanced Encryption Standard. - Size of key: 256 bits.
- Size of blocks: 128 bits.
- Size of initialization vector (IV): 128 bits.
| | cryptDES | Data Encryption Standard. - Size of key: 64-bit.
- Size of blocks: 64-bit.
- Size of initialization vector (IV): 64-bit.
Caution: this algorithm is currently deprecated. |
<Operation mode>: Optional Integer constant Process mode of blocks by the encryption algorithm used. This parameter must correspond to the operation mode used to encrypt the message. | | cryptCBC
(Default value) | Cipher Block Chaining - Sequence of blocks. | | cryptCFB | Cipher Feedback - Feedback encryption. This process mode is available if the algorithm used corresponds to the cryptAES256 constant. | | cryptCTR | Cipher Counter - Encryption based on a counter. This process mode is available if the algorithm used corresponds to the cryptAES256 constant. | | cryptECB | Electronic Code Book - Dictionary of codes. This operation mode is not recommended and it should only be used for compatibility reasons. |
<Padding>: Optional Integer constant Padding mode of encrypted data to be compatible with the size required by the encryption algorithms by blocks. This parameter must correspond to the fill mode used to encrypt the message. | | cryptPaddingPKCS
(Default value) | The data is filled with bytes whose value corresponds to the total number of bytes added to reach the requested size. | | cryptPaddingZero | The data is filled with binary zeros until the requested size is reached. |
Related Examples:
|
Unit examples (WINDEV): The encryption functions
[ + ] Using the encryption/decryption functions of WINDEV. This example is used to: - Encrypt a character string - Decrypt a character string
|
Business / UI classification: Business Logic
This page is also available for…
|
|
|
|