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CASymCipherCTR Class Reference

This class could be used for encryption/decryption of data (streams) with AES using 128bit CTR mode. More...

Inheritance diagram for CASymCipherCTR:
CASymChannelCipher CALockAble

Public Member Functions

 CASymCipherCTR ()
 
 ~CASymCipherCTR ()
 
bool isKeyValid ()
 
SINT32 setKey (const UINT8 *key)
 Sets the keys for crypt1() and crypt2() to the same key. More...
 
SINT32 setKeys (const UINT8 *key, UINT32 keysize)
 Sets the keys for crypt1() and crypt2() either to the same key (if keysize==KEY_SIZE) or to different values, if keysize==2* KEY_SIZE. More...
 
SINT32 setIVs (const UINT8 *p_iv)
 Sets iv1 and iv2 to p_iv. More...
 
SINT32 setIV2 (const UINT8 *p_iv)
 Sets iv2 to p_iv. More...
 
SINT32 crypt1 (const UINT8 *in, UINT8 *out, UINT32 len)
 Encryptes/Decrpytes in to out using iv1 and key1. More...
 
SINT32 crypt2 (const UINT8 *in, UINT8 *out, UINT32 len)
 Decryptes in to out using iv2 and key2. More...
 
- Public Member Functions inherited from CALockAble
 CALockAble ()
 
virtual ~CALockAble ()
 
SINT32 lock ()
 Locks the lockable object by threadsafe incrementing a reference counter. More...
 
SINT32 unlock ()
 Unlocks the lockable object by threadsafe decrementing a reference counter. More...
 

Protected Attributes

EVP_CIPHER_CTX * m_ctxAES1
 
EVP_CIPHER_CTX * m_ctxAES2
 
UINT8 key1 [16]
 
UINT8 key2 [16]
 
UINT8m_iv1
 
UINT8m_iv2
 
bool m_bKeySet
 

Private Attributes

CAMutexm_pcsEnc
 
CAMutexm_pcsDec
 

Additional Inherited Members

- Static Public Member Functions inherited from CASymChannelCipher
static const UINT8 *const getAlgorithmName (SYMCHANNELCIPHER_ALGORITHM alg)
 
- Protected Member Functions inherited from CALockAble
SINT32 waitForDestroy ()
 If called checks if the reference counter equals zero. More...
 

Detailed Description

This class could be used for encryption/decryption of data (streams) with AES using 128bit CTR mode.

Because of the CTR mode technical encryption and decrpytion are the same (depending on the kind of input). Therefore there is only a general crypt() function. This class has a 2-in-1 feature: Two independent IVs are available. Therefore we have crypt1() and crypt2() depending on the used IV.

Constructor & Destructor Documentation

◆ CASymCipherCTR()

CASymCipherCTR::CASymCipherCTR ( )

◆ ~CASymCipherCTR()

CASymCipherCTR::~CASymCipherCTR ( )

Member Function Documentation

◆ crypt1()

SINT32 CASymCipherCTR::crypt1 ( const UINT8 in,
UINT8 out,
UINT32  len 
)
virtual

Encryptes/Decrpytes in to out using iv1 and key1.

AES is used for encryption and the encryption is done with a special 128bit-OFB mode: In the case that (len mod 16 !=0) the unused cipher output bits are discarded and NOT used next time encryptAES() is called. That means that every time encrpytAES() is called at first new cipher output is created by calling AES-encrypt(iv).

Parameters
ininput (plain text) bytes
outoutput (encrpyted) bytes
lenlen of input. because the cipher preserves the size, len of output=len of input
Return values
E_SUCCESS

Implements CASymChannelCipher.

References E_SUCCESS, and m_ctxAES1.

Referenced by setIV2().

◆ crypt2()

SINT32 CASymCipherCTR::crypt2 ( const UINT8 in,
UINT8 out,
UINT32  len 
)
virtual

Decryptes in to out using iv2 and key2.

Parameters
ininput (encrypted) bytes
outoutput (decrpyted) bytes
lenlen of input. because the cipher preserves the size, len of output=len of input
Return values
E_SUCCESS

Implements CASymChannelCipher.

References E_SUCCESS, and m_ctxAES2.

Referenced by setIV2().

◆ isKeyValid()

bool CASymCipherCTR::isKeyValid ( )
virtual

Implements CASymChannelCipher.

References m_bKeySet, setKey(), and setKeys().

◆ setIV2()

SINT32 CASymCipherCTR::setIV2 ( const UINT8 p_iv)
virtual

Sets iv2 to p_iv.

Parameters
p_iv16 random bytes used for new iv2.
Return values
E_SUCCESS

Implements CASymChannelCipher.

References crypt1(), crypt2(), E_SUCCESS, key2, len, m_ctxAES2, and m_iv2.

◆ setIVs()

SINT32 CASymCipherCTR::setIVs ( const UINT8 p_iv)
virtual

Sets iv1 and iv2 to p_iv.

Parameters
p_iv16 random bytes used for new iv1 and iv2.
Return values
E_SUCCESS

Implements CASymChannelCipher.

References E_SUCCESS, key1, key2, m_ctxAES1, m_ctxAES2, m_iv1, and m_iv2.

◆ setKey()

SINT32 CASymCipherCTR::setKey ( const UINT8 key)
virtual

Sets the keys for crypt1() and crypt2() to the same key.

Sets the key1 and key2 used for encryption/decryption to the same value of key.

Also resets the IVs to zero!

Parameters
key16 random bytes used as key
bEncryptif true, the key should be used for encryption (otherwise it will be used for decryption)
Return values
E_SUCCESS

Implements CASymChannelCipher.

References E_SUCCESS, key1, key2, m_bKeySet, m_ctxAES1, m_ctxAES2, m_iv1, and m_iv2.

Referenced by isKeyValid(), and setKeys().

◆ setKeys()

SINT32 CASymCipherCTR::setKeys ( const UINT8 key,
UINT32  keysize 
)
virtual

Sets the keys for crypt1() and crypt2() either to the same key (if keysize==KEY_SIZE) or to different values, if keysize==2* KEY_SIZE.

Implements CASymChannelCipher.

References E_SUCCESS, E_UNKNOWN, key1, key2, KEY_SIZE, m_bKeySet, m_ctxAES1, m_ctxAES2, m_iv1, m_iv2, and setKey().

Referenced by isKeyValid().

Member Data Documentation

◆ key1

UINT8 CASymCipherCTR::key1[16]
protected

Referenced by setIVs(), setKey(), and setKeys().

◆ key2

UINT8 CASymCipherCTR::key2[16]
protected

Referenced by setIV2(), setIVs(), setKey(), and setKeys().

◆ m_bKeySet

bool CASymCipherCTR::m_bKeySet
protected

◆ m_ctxAES1

EVP_CIPHER_CTX* CASymCipherCTR::m_ctxAES1
protected

◆ m_ctxAES2

EVP_CIPHER_CTX* CASymCipherCTR::m_ctxAES2
protected

◆ m_iv1

UINT8* CASymCipherCTR::m_iv1
protected

◆ m_iv2

UINT8* CASymCipherCTR::m_iv2
protected

◆ m_pcsDec

CAMutex* CASymCipherCTR::m_pcsDec
private

Referenced by CASymCipherCTR(), and ~CASymCipherCTR().

◆ m_pcsEnc

CAMutex* CASymCipherCTR::m_pcsEnc
private

Referenced by CASymCipherCTR(), and ~CASymCipherCTR().