#include <gcm.h>

Inheritance diagram for Botan::GHASH:

Public Member Functions
void	clear () override
secure_vector< byte >	final ()
Key_Length_Specification	key_spec () const
size_t	maximum_keylength () const
size_t	minimum_keylength () const
std::string	name () const
secure_vector< byte >	nonce_hash (const byte nonce[], size_t len)
void	set_associated_data (const byte ad[], size_t ad_len)
void	set_key (const SymmetricKey &key)
template<typename Alloc >
void	set_key (const std::vector< byte, Alloc > &key)
void	set_key (const byte key[], size_t length)
void	start (const byte nonce[], size_t len)
void	update (const byte in[], size_t len)
bool	valid_keylength (size_t length) const

Detailed Description

GCM's GHASH Maybe a Transform?

Definition at line 108 of file gcm.h.

Member Function Documentation

void Botan::GHASH::clear ( ) [override, virtual]

Implements Botan::SymmetricAlgorithm.

Definition at line 145 of file gcm.cpp.

References Botan::zeroise().

   {
   zeroise(m_H);
   zeroise(m_H_ad);
   m_ghash.clear();
   m_text_len = m_ad_len = 0;
   }

secure_vector< byte > Botan::GHASH::final ( )

Definition at line 122 of file gcm.cpp.

References mac.

   {
   add_final_block(m_ghash, m_ad_len, m_text_len);

   secure_vector<byte> mac;
   mac.swap(m_ghash);

   mac ^= m_nonce;
   m_text_len = 0;
   return mac;
   }

Key_Length_Specification Botan::GHASH::key_spec ( ) const [inline, virtual]

Returns:: object describing limits on key size

Implements Botan::SymmetricAlgorithm.

Definition at line 124 of file gcm.h.

{ return Key_Length_Specification(16); }

size_t Botan::SymmetricAlgorithm::maximum_keylength ( ) const [inline, inherited]

Returns:: minimum allowed key length

Definition at line 36 of file sym_algo.h.

References Botan::Key_Length_Specification::maximum_keylength().

         {
         return key_spec().maximum_keylength();
         }

size_t Botan::SymmetricAlgorithm::minimum_keylength ( ) const [inline, inherited]

Returns:: maxmium allowed key length

Definition at line 44 of file sym_algo.h.

         {
         return key_spec().minimum_keylength();
         }

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

Implements Botan::SymmetricAlgorithm.

Definition at line 128 of file gcm.h.

{ return "GHASH"; }

secure_vector< byte > Botan::GHASH::nonce_hash	(	const byte	nonce[],
		size_t	len
	)

Definition at line 134 of file gcm.cpp.

References BOTAN_ASSERT.

   {
   BOTAN_ASSERT(m_ghash.size() == 0, "nonce_hash called during wrong time");
   secure_vector<byte> y0(16);

   ghash_update(y0, nonce, nonce_len);
   add_final_block(y0, 0, nonce_len);

   return y0;
   }

void Botan::GHASH::set_associated_data	(	const byte	ad[],
		size_t	ad_len
	)

Definition at line 97 of file gcm.cpp.

References Botan::zeroise().

   {
   zeroise(m_H_ad);

   ghash_update(m_H_ad, input, length);
   m_ad_len = length;
   }

void Botan::SymmetricAlgorithm::set_key ( const SymmetricKey & key ) [inline, inherited]

Set the symmetric key of this object.

Parameters:

key	the SymmetricKey to be set.

Definition at line 63 of file sym_algo.h.

References Botan::OctetString::begin(), and Botan::OctetString::length().

Referenced by Botan::aont_package(), Botan::aont_unpackage(), botan_mac_set_key(), Botan::TLS::Session::decrypt(), Botan::TLS::Session::encrypt(), and Botan::pbkdf2().

         {
         set_key(key.begin(), key.length());
         }

template<typename Alloc >

void Botan::SymmetricAlgorithm::set_key ( const std::vector< byte, Alloc > & key ) [inline, inherited]

Definition at line 69 of file sym_algo.h.

         {
         set_key(&key[0], key.size());
         }

void Botan::SymmetricAlgorithm::set_key	(	const byte	key[],
		size_t	length
	)		`[inline, inherited]`

Set the symmetric key of this object.

Parameters:

key	the to be set as a byte array.
length	in bytes of key param

Definition at line 79 of file sym_algo.h.

         {
         if(!valid_keylength(length))
            throw Invalid_Key_Length(name(), length);
         key_schedule(key, length);
         }

void Botan::GHASH::start	(	const byte	nonce[],
		size_t	len
	)

Definition at line 91 of file gcm.cpp.

   {
   m_nonce.assign(nonce, nonce + len);
   m_ghash = m_H_ad;
   }

void Botan::GHASH::update	(	const byte	in[],
		size_t	len
	)

Definition at line 105 of file gcm.cpp.

References BOTAN_ASSERT.

   {
   BOTAN_ASSERT(m_ghash.size() == 16, "Key was set");

   m_text_len += length;

   ghash_update(m_ghash, input, length);
   }

bool Botan::SymmetricAlgorithm::valid_keylength ( size_t length ) const [inline, inherited]

Check whether a given key length is valid for this algorithm.

Parameters:

length the key length to be checked.

Returns:: true if the key length is valid.

Definition at line 54 of file sym_algo.h.

Referenced by Botan::aont_package(), and Botan::aont_unpackage().

         {
         return key_spec().valid_keylength(length);
         }

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

src/lib/modes/aead/gcm/gcm.h
src/lib/modes/aead/gcm/gcm.cpp

Public Member Functions

Detailed Description

Member Function Documentation