Converts the password into the key. More...

#include <key.h>

Public Member Functions
const uint8_t *	getIVec (int &ivec_len) const
	Gets the pointer to the initialization vector.
const uint8_t *	getIVec () const
	Gets the initialization vector.
const uint8_t *	getKey () const
	Gets the pointer to the key.
const uint8_t *	getKey (int &key_len) const
	Gets the pointer to the key.
uint32_t	ivec_size () const
	Returns the length of the initialization vector.
	Key (const Key &k)
	Key (const char *password) throw (YAPETException)
	Initializes the key.
	operator const uint8_t * () const
	Cast operator.
	operator uint8_t * ()
	Cast operator.
bool	operator!= (const Key &k) const
	Compares two keys for inequality.
const uint8_t *	operator() () const
	Gets the pointer to the key.
const uint8_t *	operator() (int &key_len) const
	Gets the pointer to the key.
const Key &	operator= (const Key &k)
bool	operator== (const Key &k) const
	Compares two keys for equality.
uint32_t	size () const
	Returns the key length in bytes.
	~Key ()
Private Types
enum	{ KEYLENGTH = 56, MD5_LEN = 16, SHA1_LEN = 20, RIPEMD160_LEN = 20, IVECLENGTH = 8 }
Private Member Functions
void	cleanup ()
	Cleanup routine.
Private Attributes
uint8_t	IVec [IVECLENGTH]
	Holds the initialization vector.
uint8_t	key [KEYLENGTH]
	Holds the key.

Detailed Description

Converts the password into the key which is used by the other cryptographic related classes.

The key uses the maximum length of 448bits (56bytes) allowed for blowfish.

The key is computed using three passes. The first pass hashes the password using the sha1 algorithm. This hash is then re-hashed using md5 which is then appended to the key generated by the previous pass (sha1 + md5). The last pass hashes the result of the former two passes using RIPEMD-160 and appended the result to the key (sha1 + md5 + ripemd160).

The initialization vector is computed by hashing the key using the md5 algorithm and taking only the first eight bytes.

Definition at line 74 of file key.h.

Member Enumeration Documentation

anonymous enum [private]

Enumerator:

KEYLENGTH	The max length of the blowfish key in bytes (448 bits)
MD5_LEN	The length of the output of md5 (128 bits)
SHA1_LEN	The length of the output of sha1 (160 bits)
RIPEMD160_LEN	The lenght of the output of ripemd-160 (160 bits)
IVECLENGTH	The length of the initialization vector

Definition at line 76 of file key.h.

Constructor & Destructor Documentation

Key::Key ( const char * password ) throw (YAPETException)

Initializes the key and the initialization vector. Make sure you securely destroy the password provided to this method.

Parameters:

password

a pointer to the location the password is stored. The password has to be zero-terminated.

Definition at line 57 of file key.cc.

Key::Key ( const Key & k )

Definition at line 246 of file key.cc.

References IVec, IVECLENGTH, key, and KEYLENGTH.

Key::~Key ( )

Definition at line 251 of file key.cc.

References cleanup().

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Member Function Documentation

void Key::cleanup ( ) [private]

It clears the memory occupied by the key and the initialization vector by setting it to zero.

Definition at line 45 of file key.cc.

References IVec, IVECLENGTH, key, and KEYLENGTH.

Referenced by operator=(), and ~Key().

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const uint8_t* YAPET::Key::getIVec ( int & ivec_len ) const [inline]

Gets the initialization vector and its length. Please remember that the initialization vector is not \0 terminated. So make sure you read only ivec_len bytes from the pointer returned.

Parameters:

ivec_len

a reference to an integer receiving the length of the initialization vector.

Returns:: pointer to the array of unsigned 8bit integers holding the initialization vector.

Definition at line 169 of file key.h.

References IVec.

Referenced by YAPET::Crypt::decrypt(), and YAPET::Crypt::encrypt().

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const uint8_t* YAPET::Key::getIVec ( ) const [inline]

Gets the initialization vector. Please remember that the initialization vector is not \0 terminated. So make sure you read only as many bytes as returned by ivec_size().