Message digest hash functions. More...

Public Types
enum class	Alg
	Hash algorithm. More...

Public Member Functions
int	AddData (bvec_t data)
	Adds a chunk of data in a byte array to be digested by the Hash object. More...

int	AddData (std::string s)
	Adds a chunk of data in a string to be digested by the Hash object. More...

bvec_t	Final ()
	Computes final message digest for the Hash object. More...

bool	Init (Alg alg)
	Initialises the Hash object ready for repeated incremental operations. More...

Static Public Member Functions
static std::string	AlgName (Alg alg)
	Get the algorithm name as a string. More...

static bvec_t	BytesFromBytes (const bvec_t &data, Alg alg=Alg::Sha1)
	Compute hash value in byte format of byte input. More...

static bvec_t	BytesFromFile (const std::string &fileName, Alg alg=Alg::Sha1)
	Compute hash value in byte format of a binary file. More...

static std::string	HexFromBits (const bvec_t &data, int dataBitLen, Alg alg=Alg::Sha1)
	Compute hash value in hex format from bit-oriented input. More...

static std::string	HexFromBytes (const bvec_t &data, Alg alg=Alg::Sha1)
	Computes hash value in hex format of byte input. More...

static std::string	HexFromFile (const std::string &fileName, Alg alg=Alg::Sha1)
	Compute hash value in hex format of a binary file. More...

static std::string	HexFromHex (const std::string &dataHex, Alg alg=Alg::Sha1)
	Compute hash value in hex format of hex-encoded input. More...

static std::string	HexFromString (const std::string &s, Alg alg=Alg::Sha1)
	Compute hash value in hex format of string input. More...

static std::string	HexFromTextFile (const std::string &fileName, Alg alg=Alg::Sha1)
	Compute hash value in hex format of a text file, treating CR-LF pairs as a single LF. More...

static int	LengthInBytes (Alg alg)
	Get the number of bytes in the message digest for the given hash algorithm. More...

Detailed Description

Message digest hash functions.

Member Enumeration Documentation

◆ Alg

enum crsysapi::Hash::Alg

strong

Hash algorithm.

Enumerator
Sha1	SHA-1 (as per FIPS PUB 180-2)
Sha224	SHA-224 (as per FIPS PUB 180-4)
Sha256	SHA-256 (as per FIPS PUB 180-4)
Sha384	SHA-384 (as per FIPS PUB 180-4)
Sha512	SHA-512 (as per FIPS PUB 180-4)
Sha3_224	SHA-3-224 (as per FIPS PUB 202)
Sha3_256	SHA-3-256 (as per FIPS PUB 202)
Sha3_384	SHA-3-384 (as per FIPS PUB 202)
Sha3_512	SHA-3-512 (as per FIPS PUB 202)
Rmd160	RIPEMD-160
Md5	MD5 (as per RFC 1321)
Md2	MD2 (as per RFC 1319) [legacy].
Ascon_Hash	ASCON-HASH.
Ascon_HashA	ASCON-HASHA.

Member Function Documentation

◆ AddData() [1/2]

int crsysapi::Hash::AddData ( bvec_t data )

Adds a chunk of data in a byte array to be digested by the Hash object.

Parameters

data	Data to add

Returns: 0 on success or nonzero, see Gen::ErrorLookup

Exceptions

std::runtime_error if object is not valid.

◆ AddData() [2/2]

int crsysapi::Hash::AddData ( std::string s )

Adds a chunk of data in a string to be digested by the Hash object.

Parameters

s	Data to add

Returns: 0 on success or nonzero, see Gen::ErrorLookup

Exceptions

std::runtime_error if object is not valid.

◆ AlgName()

static std::string crsysapi::Hash::AlgName ( Alg alg )

static

Get the algorithm name as a string.

Parameters

alg	Hash algorithm

Returns: Name of algorithm.

Remarks: For example
cout << "Length(" << crsysapi::Hash::AlgName(crsysapi::Hash::Alg::Sha256) << ")=" << crsysapi::Hash::LengthInBytes(crsysapi::Hash::Alg::Sha256) << endl;

// Length(SHA-256)=32

crsysapi::Hash::AlgName
static std::string AlgName(Alg alg)
Get the algorithm name as a string.

crsysapi::Hash::Alg::Sha256
@ Sha256
SHA-256 (as per FIPS PUB 180-4)

crsysapi::Hash::LengthInBytes
static int LengthInBytes(Alg alg)
Get the number of bytes in the message digest for the given hash algorithm.

◆ BytesFromBytes()

static bvec_t crsysapi::Hash::BytesFromBytes	(	const bvec_t &	data,
		Alg	alg = `Alg::Sha1`
	)

static

Compute hash value in byte format of byte input.

Parameters

data	Message data in byte format
alg	Hash algorithm to be used

Returns: Message digest in byte format

◆ BytesFromFile()

static bvec_t crsysapi::Hash::BytesFromFile	(	const std::string &	fileName,
		Alg	alg = `Alg::Sha1`
	)

static

Compute hash value in byte format of a binary file.

Parameters

fileName	Name of file containing message data
alg	Hash algorithm to be used (ASCON is not supported in file mode)

Returns: Message digest in byte format

Exceptions

std::runtime_error if file does not exist or cannot be opened.

◆ Final()

bvec_t crsysapi::Hash::Final ( )

Computes final message digest for the Hash object.

Returns: Digest value in a byte array.

Remarks: This operation delivers the final result of Add operations since the Hash::Init operation. Once called, the Hash object is no longer valid. Use Hash::Init to start again.

Exceptions

std::runtime_error if object is not valid.

◆ HexFromBits()

static std::string crsysapi::Hash::HexFromBits	(	const bvec_t &	data,
		int	dataBitLen,
		Alg	alg = `Alg::Sha1`
	)

static

Compute hash value in hex format from bit-oriented input.

Parameters

data	Bit-oriented message data in byte array
dataBitLen	Number of bits in data to digest
alg	Hash algorithm to be used

Returns: Message digest in hex-encoded format

Remarks: Pass a bitstring as an array of bytes in big-endian order with the most-significant bit first. The bitstring will be truncated to the number of bits specified in dataBitLen and extraneous bits on the right will be ignored. Only the SHA family of hash functions (SHA-1, SHA-2, SHA-3) is supported in bit-oriented mode.

Exceptions

std::runtime_error if algorithm is not supported or if data is too short for the required number of bits.

◆ HexFromBytes()

static std::string crsysapi::Hash::HexFromBytes	(	const bvec_t &	data,
		Alg	alg = `Alg::Sha1`
	)

static

Computes hash value in hex format of byte input.

Parameters

data	Message data in byte format
alg	Hash algorithm to be used

Returns: Message digest in hex-encoded format

◆ HexFromFile()

static std::string crsysapi::Hash::HexFromFile	(	const std::string &	fileName,
		Alg	alg = `Alg::Sha1`
	)

static

Compute hash value in hex format of a binary file.

Parameters

fileName	Name of file containing message data
alg	Hash algorithm to be used

Returns: Message digest in hex-encoded format

Exceptions

std::runtime_error if file does not exist or cannot be opened.

◆ HexFromHex()

static std::string crsysapi::Hash::HexFromHex	(	const std::string &	dataHex,
		Alg	alg = `Alg::Sha1`
	)

static

Compute hash value in hex format of hex-encoded input.

Parameters

dataHex	Message data in hex-encoded format
alg	Hash algorithm to be used (ASCON is not supported in file mode)

Returns: Message digest in hex-encoded format

◆ HexFromString()

static std::string crsysapi::Hash::HexFromString	(	const std::string &	s,
		Alg	alg = `Alg::Sha1`
	)

static

Compute hash value in hex format of string input.

Parameters

s	Message data string
alg	Hash algorithm to be used

Returns: Message digest in hex-encoded format

◆ HexFromTextFile()

static std::string crsysapi::Hash::HexFromTextFile	(	const std::string &	fileName,
		Alg	alg = `Alg::Sha1`
	)

static

Compute hash value in hex format of a text file, treating CR-LF pairs as a single LF.

Parameters

fileName	Name of file containing message data
alg	Hash algorithm to be used

Returns: Message digest in hex format

Remarks: Use for passing message digest of file between Unix and Windows systems.

Exceptions

std::runtime_error if file does not exist or cannot be opened.

◆ Init()

bool crsysapi::Hash::Init ( Alg alg )

Initialises the Hash object ready for repeated incremental operations.

Parameters

alg	Hash algorithm to be used

Returns: True if successful.

Remarks: Only the SHA families of hash functions (SHA-1, SHA-2, SHA-3) are supported in object mode.

Exceptions

std::runtime_error if algorithm is not supported.

◆ LengthInBytes()

static int crsysapi::Hash::LengthInBytes ( Alg alg )

static

Get the number of bytes in the message digest for the given hash algorithm.

Parameters

alg	Hash algorithm

Returns: The length in bytes of the message digest output.

Public Types

Public Member Functions

Static Public Member Functions

Detailed Description

Member Enumeration Documentation

◆ Alg

Member Function Documentation

◆ AddData() [1/2]

◆ AddData() [2/2]

◆ AlgName()

◆ BytesFromBytes()

◆ BytesFromFile()

◆ Final()

◆ HexFromBits()

◆ HexFromBytes()

◆ HexFromFile()

◆ HexFromHex()

◆ HexFromString()

◆ HexFromTextFile()

◆ Init()

◆ LengthInBytes()