TElSymmetricCrypto.Decrypt method

TElSymmetricCrypto.Decrypt

Decrypts the data.

Declaration

[C#]
    void Decrypt(System.IO.Stream InStream, System.IO.Stream OutStream, int InCount);
    void Decrypt(byte[] InBuffer, int InIndex, int InSize, ref byte[] OutBuffer, int OutIndex, ref int OutSize);
    static byte[] Decrypt(int AlgID, byte[] Key, byte[] IV, TSBSymmetricCryptoMode Mode, byte[] Buffer);
    static byte[] Decrypt(int AlgID, byte[] Key, byte[] IV, TSBSymmetricCryptoMode Mode, byte[] Buffer, int Offset, int Count);

[VB.NET]
    Sub Decrypt(ByVal InStream As System.IO.Stream, ByVal OutStream As System.IO.Stream, ByVal InCount As Integer)
    Sub Decrypt(ByVal InBuffer As Byte(), ByVal InIndex As Integer, ByVal InSize As Integer, ByRef OutBuffer As Byte(), ByVal OutIndex As Integer, ByRef OutSize As Integer)
    Shared Function Decrypt(ByVal AlgID As Integer, ByVal Key As Byte(), ByVal IV As Byte(), ByVal Mode As TSBSymmetricCryptoMode, ByVal Buffer As Byte()) As Byte()
    Shared Function Decrypt(ByVal AlgID As Integer, ByVal Key As Byte(), ByVal IV As Byte(), ByVal Mode As TSBSymmetricCryptoMode, ByVal Buffer As Byte(), ByVal Offset As Integer, ByVal Count As Integer) As Byte()

[Pascal]
    procedure Decrypt(InBuffer : pointer; InSize : integer; OutBuffer : pointer; var OutSize : integer); overload;
    procedure Decrypt(InStream, OutStream : TStream; InCount : integer = 0); overload;
    class function Decrypt(AlgID : integer; const Key, IV : ByteArray; Mode : TSBSymmetricCryptoMode; Buffer : Pointer; Size : integer) : ByteArray; overload;

[C++]
    void Decrypt(void * InBuffer, int32_t InSize, void * OutBuffer, int32_t &OutSize);
    void Decrypt(TStream &InStream, TStream &OutStream, int32_t InCount);
    void Decrypt(TStream *InStream, TStream *OutStream, int32_t InCount);
    static void Decrypt(int32_t AlgID, const std::vector<uint8_t> &Key, const std::vector<uint8_t> &IV, TSBSymmetricCryptoMode Mode, void * Buffer, int32_t Size, std::vector<uint8_t> &OutResult);

[Java]
    int decrypt(byte[] InBuffer, int InIndex, int InSize, byte[][] OutBuffer, int OutIndex, int OutSize);
    static byte[] decrypt(TElSymmetricCrypto> this, int AlgID, byte[] Key, byte[] IV, TSBSymmetricCryptoMode Mode, byte[] Buffer);
    static byte[] decrypt(TElSymmetricCrypto> this, int AlgID, byte[] Key, byte[] IV, TSBSymmetricCryptoMode Mode, byte[] Buffer, int Offset, int Count);
    void decrypt(TElStream InStream, TElStream OutStream, int InCount);
    void decrypt(InputStream InStream, OutputStream OutStream, int InCount);

Parameters

AlgID - specifies the encryption algorithm.
Buffer - buffer with encrypted data.
Size - the size of the data block (in Buffer) to be decrypted.
Offset - the offset of the encrypted data block in Buffer.
Count - the number of bytes to be read from Buffer.
IV - specifies the Initial Vector.
InBuffer - buffer with encrypted data.
InIndex - the offset of the encrypted data block in InBuffer.
InSize - the size of the data block (in InBuffer) to be decrypted.
InStream - stream with encrypted data.
InCount - number of bytes to be read from InStream.
Key - the secret key.
Mode - specifies the encryption mode.
OutBuffer - buffer where the decrypted data should be stored.
OutIndex - the fffset in the OutBuffer, starting from which the data is written.
OutSize - the amount of free space in OutBuffer, in bytes.
OutStream - stream where the decrypted data will be written.

Algorithm identifier values:

Definition	Value	Description
SB_ALGORITHM_CNT_RC4	0x7001	Specifies RC4 algorithm
SB_ALGORITHM_CNT_DES	0x7002	Specifies DES algorithm
SB_ALGORITHM_CNT_3DES	0x7003	Specifies 3DES algorithm
SB_ALGORITHM_CNT_RC2	0x7004	Specifies RC2 algorithm
SB_ALGORITHM_CNT_AES128	0x7005	Specifies AES algorithm with a 128-bit key
SB_ALGORITHM_CNT_AES192	0x7006	Specifies AES algorithm with a 192-bit key
SB_ALGORITHM_CNT_AES256	0x7007	Specifies AES algorithm with a 256-bit key
SB_ALGORITHM_CNT_IDENTITY	0x700A	Specifies NO encryption. The data is returned as original.
SB_ALGORITHM_CNT_BLOWFISH	0x7010	Specifies Blowfish algorithm
SB_ALGORITHM_CNT_TWOFISH	0x7011	Specifies Twofish algorithm
SB_ALGORITHM_CNT_CAMELLIA	0x7012	Specifies Camellia algorithm
SB_ALGORITHM_CNT_CAST128	0x7013	Specifies CAST algorithm
SB_ALGORITHM_CNT_IDEA	0x7014	Specifies IDEA algorithm
SB_ALGORITHM_CNT_SERPENT	0x7015	Specifies Serpent algorithm
SB_ALGORITHM_CNT_TWOFISH128	0x7016	Specifies Twofish algorithm with a 128-bit key
SB_ALGORITHM_CNT_TWOFISH192	0x7017	Specifies Twofish algorithm with a 192-bit key
SB_ALGORITHM_CNT_TWOFISH256	0x7018	Specifies Twofish algorithm with a 256-bit key
SB_ALGORITHM_CNT_CAMELLIA128	0x7019	Specifies Camellia algorithm with a 128-bit key
SB_ALGORITHM_CNT_CAMELLIA192	0x701A	Specifies Camellia algorithm with a 192-bit key
SB_ALGORITHM_CNT_CAMELLIA256	0x701B	Specifies Camellia algorithm with a 256-bit key
SB_ALGORITHM_CNT_SERPENT128	0x701C	Specifies Serpent algorithm with a 128-bit key
SB_ALGORITHM_CNT_SERPENT192	0x701D	Specifies Serpent algorithm with a 192-bit key
SB_ALGORITHM_CNT_SERPENT256	0x701E	Specifies Serpent algorithm with a 256-bit key
SB_ALGORITHM_CNT_SEED	0x7020	Specifies SEED algorithm
SB_ALGORITHM_CNT_RABBIT	0x7021	Specifies Rabbit algorithm
SB_ALGORITHM_CNT_SYMMETRIC	0x7022	A general value for a symmetric algorithm
SB_ALGORITHM_CNT_GOST_28147_1989	0x7023	GOST 28147-89 algorithm
SB_ALGORITHM_AEAD_CHACHA20_POLY1305	0x7501	ChaCha20-Poly1305
SB_ALGORITHM_AEAD_AES128_GCM	0x7502	AEAD_AES_128_GCM algorithm as defined in RFC 5116
SB_ALGORITHM_AEAD_AES192_GCM	0x7503	AEAD_AES_192_GCM
SB_ALGORITHM_AEAD_AES256_GCM	0x7504	AEAD_AES256_GCM algorithm as defined in RFC 5116
SB_ALGORITHM_AEAD_AES128_CCM	0x7505	AEAD_AES128_CCM algorithm as defined in RFC 5116
SB_ALGORITHM_AEAD_AES192_CCM	0x7506	AEAD_AES192_CCM
SB_ALGORITHM_AEAD_AES256_CCM	0x7507	AEAD_AES256_CCM algorithm as defined in RFC 5116

Mode values:

[.NET]	[Pascal]	[C++]	Description
cmDefault = 0	cmDefault	_cmDefault = 0	Default encryption mode for block ciphers. Currently CBC is default mode. For stream ciphers Default is the only mode
cmECB = 1	cmECB	_cmECB = 1	ECB encryption mode
cmCBC = 2	cmCBC	_cmCBC = 2	CBC encryption mode
cmCTR = 3	cmCTR	_cmCTR = 3	CTR encryption mode
cmCFB8 = 4	cmCFB8	_cmCFB8 = 4	CFB8 encryption mode
cmGCM = 5	cmGCM	_cmGCM = 5	GCM encryption mode
cmCCM = 6	cmCCM	_cmCCM = 6	CCM encryption mode

Return value

Returns the decrypted data.

Description

Use this method when you want to decrypt the data and you have all data for decryption at hand. This method is a shorthand for InitializeDecryption / DecryptUdpdate / FinalizeDecryption sequence of calls.

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