#include <comb4p.h>

Inheritance diagram for Botan::Comb4P:

Public Types
typedef SCAN_Name	Spec
Public Member Functions
void	clear ()
HashFunction *	clone () const
	Comb4P (HashFunction h1, HashFunction h2)
void	final (byte out[])
secure_vector< byte >	final ()
template<typename Alloc >
void	final (std::vector< byte, Alloc > &out)
size_t	hash_block_size () const
std::string	name () const
size_t	output_length () const
secure_vector< byte >	process (const byte in[], size_t length)
secure_vector< byte >	process (const secure_vector< byte > &in)
secure_vector< byte >	process (const std::vector< byte > &in)
secure_vector< byte >	process (const std::string &in)
void	update (const byte in[], size_t length)
void	update (const secure_vector< byte > &in)
void	update (const std::vector< byte > &in)
void	update (const std::string &str)
void	update (byte in)
template<typename T >
void	update_be (const T in)
Static Public Member Functions
static Comb4P *	make (const Spec &spec)

Detailed Description

Combines two hash functions using a Feistel scheme. Described in "On the Security of Hash Function Combiners", Anja Lehmann

Definition at line 19 of file comb4p.h.

Member Typedef Documentation

typedef SCAN_Name Botan::HashFunction::Spec [inherited]

Definition at line 37 of file hash.h.

Constructor & Destructor Documentation

Botan::Comb4P::Comb4P	(	HashFunction *	h1,
		HashFunction *	h2
	)

Parameters:

h1	the first hash
h2	the second hash

Definition at line 54 of file comb4p.cpp.

References clear().

Referenced by make().

                                                 :
   m_hash1(h1), m_hash2(h2)
   {
   if(m_hash1->name() == m_hash2->name())
      throw std::invalid_argument("Comb4P: Must use two distinct hashes");

   if(m_hash1->output_length() != m_hash2->output_length())
      throw std::invalid_argument("Comb4P: Incompatible hashes " +
                                  m_hash1->name() + " and " +
                                  m_hash2->name());

   clear();
   }

Member Function Documentation

void Botan::Comb4P::clear ( ) [virtual]

Implements Botan::HashFunction.

Definition at line 80 of file comb4p.cpp.

Referenced by Comb4P().

   {
   m_hash1->clear();
   m_hash2->clear();

   // Prep for processing next message, if any
   m_hash1->update(0);
   m_hash2->update(0);
   }

HashFunction* Botan::Comb4P::clone ( ) const [inline, virtual]

Returns:: new object representing the same algorithm as *this

Implements Botan::HashFunction.

Definition at line 37 of file comb4p.h.

         {
         return new Comb4P(m_hash1->clone(), m_hash2->clone());
         }

void Botan::Buffered_Computation::final ( byte out[] ) [inline, inherited]

Complete the computation and retrieve the final result.

Parameters:

out	The byte array to be filled with the result. Must be of length output_length()

Definition at line 90 of file buf_comp.h.

Referenced by botan_hash_final(), botan_mac_final(), Botan::McEliece_KEM_Decryptor::decrypt(), Botan::TLS::Session::decrypt(), Botan::McEliece_KEM_Encryptor::encrypt(), Botan::TLS::Session::encrypt(), Botan::mgf1_mask(), Botan::pbkdf2(), and Botan::TLS::write_record().

{ final_result(out); }

secure_vector<byte> Botan::Buffered_Computation::final ( ) [inline, inherited]

Complete the computation and retrieve the final result.

Returns:: secure_vector holding the result

Definition at line 97 of file buf_comp.h.

         {
         secure_vector<byte> output(output_length());
         final_result(&output[0]);
         return output;
         }

template<typename Alloc >

void Botan::Buffered_Computation::final ( std::vector< byte, Alloc > & out ) [inline, inherited]

Definition at line 105 of file buf_comp.h.

         {
         out.resize(output_length());
         final_result(&out[0]);
         }

size_t Botan::Comb4P::hash_block_size ( ) const [virtual]

Returns:: hash block size as defined for this algorithm

Reimplemented from Botan::HashFunction.

Definition at line 68 of file comb4p.cpp.

   {
   if(m_hash1->hash_block_size() == m_hash2->hash_block_size())
      return m_hash1->hash_block_size();

   /*
   * Return LCM of the block sizes? This would probably be OK for
   * HMAC, which is the main thing relying on knowing the block size.
   */
   return 0;
   }

Comb4P * Botan::Comb4P::make ( const Spec & spec ) [static]

Definition at line 40 of file comb4p.cpp.

References Botan::SCAN_Name::arg(), Botan::SCAN_Name::arg_count(), and Comb4P().

   {
   if(spec.arg_count() == 2)
      {
      auto& hashes = Algo_Registry<HashFunction>::global_registry();
      std::unique_ptr<HashFunction> h1(hashes.make(spec.arg(0)));
      std::unique_ptr<HashFunction> h2(hashes.make(spec.arg(1)));

      if(h1 && h2)
         return new Comb4P(h1.release(), h2.release());
      }
   return nullptr;
   }

std::string Botan::Comb4P::name ( ) const [inline, virtual]

Implements Botan::HashFunction.

Definition at line 42 of file comb4p.h.

References name().

Referenced by name().

         {
         return "Comb4P(" + m_hash1->name() + "," + m_hash2->name() + ")";
         }

size_t Botan::Comb4P::output_length ( ) const [inline, virtual]

Returns:: length of the output of this function in bytes

Implements Botan::Buffered_Computation.

Definition at line 30 of file comb4p.h.

         {
         return m_hash1->output_length() + m_hash2->output_length();
         }

secure_vector<byte> Botan::Buffered_Computation::process	(	const byte	in[],
		size_t	length
	)		`[inline, inherited]`

Update and finalize computation. Does the same as calling update() and final() consecutively.

Parameters:

in	the input to process as a byte array
length	the length of the byte array

Returns:: the result of the call to final()

Definition at line 118 of file buf_comp.h.

Referenced by Botan::HMAC_RNG::HMAC_RNG(), Botan::RTSS_Share::split(), and Botan::Cert_Extension::Subject_Key_ID::Subject_Key_ID().

         {
         add_data(in, length);
         return final();
         }

secure_vector<byte> Botan::Buffered_Computation::process ( const secure_vector< byte > & in ) [inline, inherited]

Update and finalize computation. Does the same as calling update() and final() consecutively.

Parameters:

in	the input to process

Returns:: the result of the call to final()

Definition at line 130 of file buf_comp.h.

         {
         add_data(&in[0], in.size());
         return final();
         }

secure_vector<byte> Botan::Buffered_Computation::process ( const std::vector< byte > & in ) [inline, inherited]

Update and finalize computation. Does the same as calling update() and final() consecutively.

Parameters:

in	the input to process

Returns:: the result of the call to final()

Definition at line 142 of file buf_comp.h.

         {
         add_data(&in[0], in.size());
         return final();
         }

secure_vector<byte> Botan::Buffered_Computation::process ( const std::string & in ) [inline, inherited]

Update and finalize computation. Does the same as calling update() and final() consecutively.

Parameters:

in	the input to process as a string

Returns:: the result of the call to final()

Definition at line 154 of file buf_comp.h.

         {
         update(in);
         return final();
         }

void Botan::Buffered_Computation::update	(	const byte	in[],
		size_t	length
	)		`[inline, inherited]`

Add new input to process.

Parameters:

in	the input to process as a byte array
length	of param in in bytes

Definition at line 34 of file buf_comp.h.

Referenced by botan_hash_update(), botan_mac_update(), Botan::McEliece_KEM_Decryptor::decrypt(), Botan::TLS::Session::decrypt(), Botan::McEliece_KEM_Encryptor::encrypt(), Botan::TLS::Session::encrypt(), Botan::mgf1_mask(), Botan::pbkdf2(), and Botan::TLS::write_record().

{ add_data(in, length); }

void Botan::Buffered_Computation::update ( const secure_vector< byte > & in ) [inline, inherited]

Add new input to process.

Parameters:

in	the input to process as a secure_vector

Definition at line 40 of file buf_comp.h.

         {
         add_data(&in[0], in.size());
         }

void Botan::Buffered_Computation::update ( const std::vector< byte > & in ) [inline, inherited]

Add new input to process.

Parameters:

in	the input to process as a std::vector

Definition at line 49 of file buf_comp.h.

         {
         add_data(&in[0], in.size());
         }

void Botan::Buffered_Computation::update ( const std::string & str ) [inline, inherited]

Add new input to process.

Parameters:

str	the input to process as a std::string. Will be interpreted as a byte array based on the strings encoding.

Definition at line 73 of file buf_comp.h.

         {
         add_data(reinterpret_cast<const byte*>(str.data()), str.size());
         }

void Botan::Buffered_Computation::update ( byte in ) [inline, inherited]

Process a single byte.

Parameters:

in	the byte to process

Definition at line 82 of file buf_comp.h.

{ add_data(&in, 1); }

template<typename T >

void Botan::Buffered_Computation::update_be ( const T in ) [inline, inherited]

Add an integer in big-endian order

Parameters:

in the value

Definition at line 58 of file buf_comp.h.

References Botan::get_byte().

Referenced by Botan::mgf1_mask(), and Botan::pbkdf2().

         {
         for(size_t i = 0; i != sizeof(T); ++i)
            {
            byte b = get_byte(i, in);
            add_data(&b, 1);
            }
         }

The documentation for this class was generated from the following files:

src/lib/hash/comb4p/comb4p.h
src/lib/hash/comb4p/comb4p.cpp

Public Types

Public Member Functions

Static Public Member Functions

Detailed Description

Member Typedef Documentation

Constructor & Destructor Documentation

Member Function Documentation