#include <cfb.h>

Inheritance diagram for Botan::CFB_Decryption:

Public Member Functions
bool	authenticated () const

	CFB_Decryption (std::unique_ptr< BlockCipher > cipher, size_t feedback_bits)

void	clear () override final

size_t	default_nonce_length () const override final

void	finish (secure_vector< uint8_t > &final_block, size_t offset=0)

template<concepts::resizable_byte_buffer T>
void	finish (T &final_block, size_t offset=0)

bool	has_keying_material () const override final

size_t	ideal_granularity () const override final

Key_Length_Specification	key_spec () const override final

size_t	maximum_keylength () const

size_t	minimum_final_size () const override final

size_t	minimum_keylength () const

std::string	name () const override final

size_t	output_length (size_t input_length) const override final

size_t	process (std::span< uint8_t > msg)

size_t	process (uint8_t msg[], size_t msg_len)

virtual std::string	provider () const

virtual bool	requires_entire_message () const

void	reset () override final

void	set_key (const SymmetricKey &key)

void	set_key (const uint8_t key[], size_t length)

void	set_key (std::span< const uint8_t > key)

void	start ()

void	start (const uint8_t nonce[], size_t nonce_len)

void	start (std::span< const uint8_t > nonce)

virtual size_t	tag_size () const

template<concepts::resizable_byte_buffer T>
void	update (T &buffer, size_t offset=0)

size_t	update_granularity () const override final

bool	valid_keylength (size_t length) const

bool	valid_nonce_length (size_t n) const override final

Static Public Member Functions
static std::unique_ptr< Cipher_Mode >	create (std::string_view algo, Cipher_Dir direction, std::string_view provider="")

static std::unique_ptr< Cipher_Mode >	create_or_throw (std::string_view algo, Cipher_Dir direction, std::string_view provider="")

static std::vector< std::string >	providers (std::string_view algo_spec)

Protected Member Functions
void	assert_key_material_set () const

void	assert_key_material_set (bool predicate) const

size_t	block_size () const

const BlockCipher &	cipher () const

size_t	feedback () const

void	shift_register ()

Protected Attributes
secure_vector< uint8_t >	m_keystream

size_t	m_keystream_pos = 0

secure_vector< uint8_t >	m_state

Detailed Description

CFB Decryption

Definition at line 89 of file cfb.h.

Constructor & Destructor Documentation

◆ CFB_Decryption()

Botan::CFB_Decryption::CFB_Decryption	(	std::unique_ptr< BlockCipher >	cipher,
		size_t	feedback_bits
	)

inline

If feedback_bits is zero, cipher->block_size() bytes will be used.

Parameters

cipher	block cipher to use
feedback_bits	number of bits fed back into the shift register, must be a multiple of 8

Definition at line 98 of file cfb.h.

98 :

99 CFB_Mode(std::move(cipher), feedback_bits) {}

Botan::CFB_Mode::CFB_Mode

CFB_Mode(std::unique_ptr< BlockCipher > cipher, size_t feedback_bits)

Definition: cfb.cpp:14

Botan::CFB_Mode::cipher

const BlockCipher & cipher() const

Definition: cfb.h:50

Member Function Documentation

◆ assert_key_material_set() [1/2]

void Botan::SymmetricAlgorithm::assert_key_material_set ( ) const

inlineprotectedinherited

Definition at line 182 of file sym_algo.h.

         {
         assert_key_material_set(has_keying_material());
         }

◆ assert_key_material_set() [2/2]

void Botan::SymmetricAlgorithm::assert_key_material_set ( bool predicate ) const

inlineprotectedinherited

Definition at line 187 of file sym_algo.h.

         {
         if(!predicate)
            throw_key_not_set_error();
         }

◆ authenticated()

bool Botan::Cipher_Mode::authenticated ( ) const

inlineinherited

Returns: true iff this mode provides authentication as well as confidentiality.

Definition at line 239 of file cipher_mode.h.

239{ return this->tag_size() > 0; }

Botan::Cipher_Mode::tag_size

virtual size_t tag_size() const

Definition: cipher_mode.h:244

◆ block_size()

size_t Botan::CFB_Mode::block_size ( ) const

inlineprotectedinherited

Definition at line 51 of file cfb.h.

51{ return m_block_size; }

Referenced by Botan::CFB_Mode::default_nonce_length(), Botan::CFB_Mode::name(), Botan::CFB_Mode::shift_register(), and Botan::CFB_Mode::valid_nonce_length().

◆ cipher()

const BlockCipher & Botan::CFB_Mode::cipher ( ) const

inlineprotectedinherited

Definition at line 50 of file cfb.h.

50{ return *m_cipher; }

Referenced by Botan::CFB_Mode::key_spec(), Botan::CFB_Mode::name(), and Botan::CFB_Mode::shift_register().

◆ clear()

void Botan::CFB_Mode::clear ( )

finaloverridevirtualinherited

Reset the internal state. This includes not just the key, but any partial message that may have been in process.

Implements Botan::SymmetricAlgorithm.

Definition at line 25 of file cfb.cpp.

   {
   m_cipher->clear();
   m_keystream.clear();
   reset();
   }

References Botan::CFB_Mode::m_keystream, and Botan::CFB_Mode::reset().

◆ create()

std::unique_ptr< Cipher_Mode > Botan::Cipher_Mode::create	(	std::string_view	algo,
		Cipher_Dir	direction,
		std::string_view	provider = `""`
	)

staticinherited

Create an AEAD mode

Parameters

algo	the algorithm to create
direction	specify if this should be an encryption or decryption AEAD
provider	optional specification for provider to use

Returns: an AEAD mode or a null pointer if not available

Definition at line 50 of file cipher_mode.cpp.

   {
#if defined(BOTAN_HAS_COMMONCRYPTO)
   if(provider.empty() || provider == "commoncrypto")
      {
      auto commoncrypto_cipher = make_commoncrypto_cipher_mode(algo, direction);
 
      if(commoncrypto_cipher)
         return commoncrypto_cipher;
 
      if(!provider.empty())
         return std::unique_ptr<Cipher_Mode>();
      }
#endif
 
#if defined(BOTAN_HAS_STREAM_CIPHER)
   if(auto sc = StreamCipher::create(algo))
      {
      return std::make_unique<Stream_Cipher_Mode>(std::move(sc));
      }
#endif
 
#if defined(BOTAN_HAS_AEAD_MODES)
   if(auto aead = AEAD_Mode::create(algo, direction))
      {
      return aead;
      }
#endif
 
   if(algo.find('/') != std::string::npos)
      {
      const std::vector<std::string> algo_parts = split_on(algo, '/');
      std::string_view cipher_name = algo_parts[0];
      const std::vector<std::string> mode_info = parse_algorithm_name(algo_parts[1]);
 
      if(mode_info.empty())
         return std::unique_ptr<Cipher_Mode>();
 
      std::ostringstream mode_name;
 
      mode_name << mode_info[0] << '(' << cipher_name;
      for(size_t i = 1; i < mode_info.size(); ++i)
         mode_name << ',' << mode_info[i];
      for(size_t i = 2; i < algo_parts.size(); ++i)
         mode_name << ',' << algo_parts[i];
      mode_name << ')';
 
      return Cipher_Mode::create(mode_name.str(), direction, provider);
      }
 
#if defined(BOTAN_HAS_BLOCK_CIPHER)
 
   SCAN_Name spec(algo);
 
   if(spec.arg_count() == 0)
      {
      return std::unique_ptr<Cipher_Mode>();
      }
 
   auto bc = BlockCipher::create(spec.arg(0), provider);
 
   if(!bc)
      {
      return std::unique_ptr<Cipher_Mode>();
      }
 
#if defined(BOTAN_HAS_MODE_CBC)
   if(spec.algo_name() == "CBC")
      {
      const std::string padding = spec.arg(1, "PKCS7");
 
      if(padding == "CTS")
         {
         if(direction == Cipher_Dir::Encryption)
            return std::make_unique<CTS_Encryption>(std::move(bc));
         else
            return std::make_unique<CTS_Decryption>(std::move(bc));
         }
      else
         {
         auto pad = BlockCipherModePaddingMethod::create(padding);
 
         if(pad)
            {
            if(direction == Cipher_Dir::Encryption)
               return std::make_unique<CBC_Encryption>(std::move(bc), std::move(pad));
            else
               return std::make_unique<CBC_Decryption>(std::move(bc), std::move(pad));
            }
         }
      }
#endif
 
#if defined(BOTAN_HAS_MODE_XTS)
   if(spec.algo_name() == "XTS")
      {
      if(direction == Cipher_Dir::Encryption)
         return std::make_unique<XTS_Encryption>(std::move(bc));
      else
         return std::make_unique<XTS_Decryption>(std::move(bc));
      }
#endif
 
#if defined(BOTAN_HAS_MODE_CFB)
   if(spec.algo_name() == "CFB")
      {
      const size_t feedback_bits = spec.arg_as_integer(1, 8*bc->block_size());
      if(direction == Cipher_Dir::Encryption)
         return std::make_unique<CFB_Encryption>(std::move(bc), feedback_bits);
      else
         return std::make_unique<CFB_Decryption>(std::move(bc), feedback_bits);
      }
#endif
 
#endif
 
   return std::unique_ptr<Cipher_Mode>();
   }

References Botan::SCAN_Name::algo_name(), Botan::SCAN_Name::arg(), Botan::SCAN_Name::arg_as_integer(), Botan::SCAN_Name::arg_count(), Botan::AEAD_Mode::create(), Botan::Cipher_Mode::create(), Botan::BlockCipherModePaddingMethod::create(), Botan::BlockCipher::create(), Botan::StreamCipher::create(), Botan::Encryption, Botan::make_commoncrypto_cipher_mode(), Botan::parse_algorithm_name(), Botan::Cipher_Mode::provider(), and Botan::split_on().

Referenced by botan_cipher_init(), Botan::Cipher_Mode::create(), Botan::Cipher_Mode::create_or_throw(), Botan::get_cipher_mode(), Botan::pbes2_decrypt(), and Botan::Cipher_Mode::providers().

◆ create_or_throw()

std::unique_ptr< Cipher_Mode > Botan::Cipher_Mode::create_or_throw	(	std::string_view	algo,
		Cipher_Dir	direction,
		std::string_view	provider = `""`
	)

staticinherited

Create an AEAD mode, or throw

Parameters

algo	the algorithm to create
direction	specify if this should be an encryption or decryption AEAD
provider	optional specification for provider to use

Returns: an AEAD mode, or throw an exception

Definition at line 40 of file cipher_mode.cpp.

   {
   if(auto mode = Cipher_Mode::create(algo, direction, provider))
      return mode;
 
   throw Lookup_Error("Cipher mode", algo, provider);
   }

References Botan::Cipher_Mode::create(), and Botan::Cipher_Mode::provider().

Referenced by Botan::ECIES_System_Params::create_cipher(), Botan::CryptoBox::decrypt_bin(), Botan::CryptoBox::encrypt(), and Botan::get_cipher().

◆ default_nonce_length()

size_t Botan::CFB_Mode::default_nonce_length ( ) const

finaloverridevirtualinherited

Returns: the default size for a nonce

Implements Botan::Cipher_Mode.

Definition at line 72 of file cfb.cpp.

   {
   return block_size();
   }

References Botan::CFB_Mode::block_size().

◆ feedback()

size_t Botan::CFB_Mode::feedback ( ) const

inlineprotectedinherited

Definition at line 49 of file cfb.h.

49{ return m_feedback_bytes; }

Referenced by Botan::CFB_Mode::CFB_Mode(), Botan::CFB_Mode::ideal_granularity(), Botan::CFB_Mode::name(), Botan::CFB_Mode::shift_register(), and Botan::CFB_Mode::update_granularity().

◆ finish() [1/2]

void Botan::Cipher_Mode::finish	(	secure_vector< uint8_t > &	final_block,
		size_t	offset = `0`
	)

inlineinherited

Complete processing of a message.

Parameters

final_block	in/out parameter which must be at least minimum_final_size() bytes, and will be set to any final output
offset	an offset into final_block to begin processing

Definition at line 158 of file cipher_mode.h.

         {
         finish_msg(final_block, offset);
         }

Referenced by botan_cipher_update(), and Botan::TLS::write_record().

◆ finish() [2/2]

template<concepts::resizable_byte_buffer T>

void Botan::Cipher_Mode::finish	(	T &	final_block,
		size_t	offset = `0`
	)

inlineinherited

Complete procession of a message.

Note: Using this overload with anything but a Botan::secure_vector<> is copying the bytes in the in/out buffer.

Parameters

final_block	in/out parameter which must be at least minimum_final_size() bytes, and will be set to any final output
offset	an offset into final_block to begin processing

Definition at line 174 of file cipher_mode.h.

         {
         Botan::secure_vector<uint8_t> tmp(final_block.begin(), final_block.end());
         finish_msg(tmp, offset);
         final_block.resize(tmp.size());
         std::copy(tmp.begin(), tmp.end(), final_block.begin());
         }

◆ has_keying_material()

bool Botan::CFB_Mode::has_keying_material ( ) const

finaloverridevirtualinherited

Returns: true if a key has been set on this object

Implements Botan::SymmetricAlgorithm.

Definition at line 82 of file cfb.cpp.

   {
   return m_cipher->has_keying_material();
   }

◆ ideal_granularity()

size_t Botan::CFB_Mode::ideal_granularity ( ) const

finaloverridevirtualinherited

Return an ideal granularity. This will be a multiple of the result of update_granularity but may be larger. If so it indicates that better performance may be achieved by providing buffers that are at least that size.

Implements Botan::Cipher_Mode.

Definition at line 56 of file cfb.cpp.

   {
   // Multiplier here is arbitrary
   return 16*feedback();
   }

References Botan::CFB_Mode::feedback().

◆ key_spec()

Key_Length_Specification Botan::CFB_Mode::key_spec ( ) const

finaloverridevirtualinherited

Returns: object describing limits on key size

Implements Botan::SymmetricAlgorithm.

Definition at line 67 of file cfb.cpp.

   {
   return cipher().key_spec();
   }

References Botan::CFB_Mode::cipher(), and Botan::SymmetricAlgorithm::key_spec().

◆ maximum_keylength()

size_t Botan::SymmetricAlgorithm::maximum_keylength ( ) const

inlineinherited

Returns: maximum allowed key length

Definition at line 123 of file sym_algo.h.

         {
         return key_spec().maximum_keylength();
         }

◆ minimum_final_size()

size_t Botan::CFB_Mode::minimum_final_size ( ) const

finaloverridevirtualinherited

Returns: required minimium size to finalize() - may be any length larger than this.

Implements Botan::Cipher_Mode.

Definition at line 62 of file cfb.cpp.

   {
   return 0;
   }

◆ minimum_keylength()

size_t Botan::SymmetricAlgorithm::minimum_keylength ( ) const

inlineinherited

Returns: minimum allowed key length

Definition at line 131 of file sym_algo.h.

         {
         return key_spec().minimum_keylength();
         }

◆ name()

std::string Botan::CFB_Mode::name ( ) const

finaloverridevirtualinherited

Returns: the algorithm name

Implements Botan::SymmetricAlgorithm.

Definition at line 38 of file cfb.cpp.

   {
   if(feedback() == cipher().block_size())
      return fmt("{}/CFB", cipher().name());
   else
      return fmt("{}/CFB({})", cipher().name(), feedback()*8);
   }

References Botan::CFB_Mode::block_size(), Botan::CFB_Mode::cipher(), Botan::CFB_Mode::feedback(), Botan::fmt(), and Botan::CFB_Mode::name().

Referenced by Botan::CFB_Mode::CFB_Mode(), and Botan::CFB_Mode::name().

◆ output_length()

size_t Botan::CFB_Mode::output_length ( size_t input_length ) const

finaloverridevirtualinherited

Returns the size of the output if this transform is used to process a message with input_length bytes. In most cases the answer is precise. If it is not possible to precise (namely for CBC decryption) instead an upper bound is returned.

Implements Botan::Cipher_Mode.

Definition at line 46 of file cfb.cpp.

   {
   return input_length;
   }

◆ process() [1/2]

size_t Botan::Cipher_Mode::process ( std::span< uint8_t > msg )

inlineinherited

Process message blocks

Input must be a multiple of update_granularity

Processes msg in place and returns bytes written. Normally this will be either msg_len (indicating the entire message was processed) or for certain AEAD modes zero (indicating that the mode requires the entire message be processed in one pass).

Parameters

msg	the message to be processed

Returns: bytes written in-place

Definition at line 133 of file cipher_mode.h.

134 { return this->process_msg(msg.data(), msg.size()); }

Botan::Cipher_Mode::process_msg

virtual size_t process_msg(uint8_t msg[], size_t msg_len)=0

◆ process() [2/2]

size_t Botan::Cipher_Mode::process	(	uint8_t	msg[],
		size_t	msg_len
	)

inlineinherited

Definition at line 135 of file cipher_mode.h.

136 { return this->process_msg(msg, msg_len); }

◆ provider()

virtual std::string Botan::Cipher_Mode::provider ( ) const

inlinevirtualinherited

Returns: provider information about this implementation. Default is "base", might also return "sse2", "avx2", "openssl", or some other arbitrary string.

Reimplemented in Botan::GCM_Mode.

Definition at line 250 of file cipher_mode.h.

250{ return "base"; }

Referenced by Botan::AEAD_Mode::create(), Botan::Cipher_Mode::create(), Botan::AEAD_Mode::create_or_throw(), and Botan::Cipher_Mode::create_or_throw().

◆ providers()

std::vector< std::string > Botan::Cipher_Mode::providers ( std::string_view algo_spec )

staticinherited

Returns: list of available providers for this algorithm, empty if not available

Parameters

algo_spec algorithm name

Definition at line 172 of file cipher_mode.cpp.

   {
   const std::vector<std::string>& possible = { "base", "commoncrypto" };
   std::vector<std::string> providers;
   for(auto&& prov : possible)
      {
      auto mode = Cipher_Mode::create(algo_spec, Cipher_Dir::Encryption, prov);
      if(mode)
         {
         providers.push_back(prov); // available
         }
      }
   return providers;
   }

References Botan::Cipher_Mode::create(), Botan::Encryption, and Botan::Cipher_Mode::providers().

Referenced by Botan::Cipher_Mode::providers().

◆ requires_entire_message()

virtual bool Botan::Cipher_Mode::requires_entire_message ( ) const

inlinevirtualinherited

Certain modes require the entire message be available before any processing can occur. For such modes, input will be consumed but not returned, until finish is called, which returns the entire message.

This function returns true if this mode has this style of operation.

Reimplemented in Botan::CCM_Mode, and Botan::SIV_Mode.

Definition at line 212 of file cipher_mode.h.

212{ return false; }

◆ reset()

void Botan::CFB_Mode::reset ( )

finaloverridevirtualinherited

Resets just the message specific state and allows encrypting again under the existing key

Implements Botan::Cipher_Mode.

Definition at line 32 of file cfb.cpp.

   {
   m_state.clear();
   zeroise(m_keystream);
   }

References Botan::CFB_Mode::m_keystream, Botan::CFB_Mode::m_state, and Botan::zeroise().

Referenced by Botan::CFB_Mode::clear().

◆ set_key() [1/3]

void Botan::SymmetricAlgorithm::set_key ( const SymmetricKey & key )

inlineinherited

Set the symmetric key of this object.

Parameters

key	the SymmetricKey to be set.

Definition at line 150 of file sym_algo.h.

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

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

Referenced by Botan::Sodium::crypto_stream_salsa20(), Botan::Sodium::crypto_stream_salsa20_xor_ic(), Botan::Sodium::crypto_stream_xsalsa20(), Botan::Sodium::crypto_stream_xsalsa20_xor_ic(), Botan::FPE::fe1_decrypt(), Botan::FPE::fe1_encrypt(), and Botan::Sodium::randombytes_buf_deterministic().

◆ set_key() [2/3]

void Botan::SymmetricAlgorithm::set_key	(	const uint8_t	key[],
		size_t	length
	)

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 17 of file sym_algo.cpp.

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

References Botan::SymmetricAlgorithm::name(), and Botan::SymmetricAlgorithm::valid_keylength().

◆ set_key() [3/3]

void Botan::SymmetricAlgorithm::set_key ( std::span< const uint8_t > key )

inlineinherited

Set the symmetric key of this object.

Parameters

key	the contiguous byte range to be set.

Definition at line 159 of file sym_algo.h.

         {
         set_key(key.data(), key.size());
         }

◆ shift_register()

void Botan::CFB_Mode::shift_register ( )

protectedinherited

Definition at line 116 of file cfb.cpp.

   {
   const size_t shift = feedback();
   const size_t carryover = block_size() - shift;
 
   if(carryover > 0)
      {
      copy_mem(m_state.data(), &m_state[shift], carryover);
      }
   copy_mem(&m_state[carryover], m_keystream.data(), shift);
   cipher().encrypt(m_state, m_keystream);
   m_keystream_pos = 0;
   }

References Botan::CFB_Mode::block_size(), Botan::CFB_Mode::cipher(), Botan::copy_mem(), Botan::BlockCipher::encrypt(), Botan::CFB_Mode::feedback(), Botan::CFB_Mode::m_keystream, Botan::CFB_Mode::m_keystream_pos, and Botan::CFB_Mode::m_state.

◆ start() [1/3]

void Botan::Cipher_Mode::start ( )

inlineinherited

Begin processing a message.

The exact semantics of this depend on the mode. For many modes, the call will fail since a nonce must be provided.

For certain modes such as CBC this will instead cause the last ciphertext block to be used as the nonce of the new message; doing this isn't a good idea, but some (mostly older) protocols do this.

Definition at line 115 of file cipher_mode.h.

         {
         return start_msg(nullptr, 0);
         }

◆ start() [2/3]

void Botan::Cipher_Mode::start	(	const uint8_t	nonce[],
		size_t	nonce_len
	)

inlineinherited

Begin processing a message with a fresh nonce.

Parameters

nonce	the per message nonce
nonce_len	length of nonce

Definition at line 100 of file cipher_mode.h.

         {
         start_msg(nonce, nonce_len);
         }

◆ start() [3/3]

void Botan::Cipher_Mode::start ( std::span< const uint8_t > nonce )

inlineinherited

Begin processing a message with a fresh nonce.

Parameters

nonce the per message nonce

Definition at line 90 of file cipher_mode.h.

         {
         start_msg(nonce.data(), nonce.size());
         }

Referenced by botan_cipher_start(), and Botan::TLS::write_record().

◆ tag_size()

virtual size_t Botan::Cipher_Mode::tag_size ( ) const

inlinevirtualinherited

Returns: the size of the authentication tag used (in bytes)

Reimplemented in Botan::ChaCha20Poly1305_Mode, Botan::CCM_Mode, Botan::EAX_Mode, Botan::GCM_Mode, Botan::OCB_Mode, Botan::SIV_Mode, and Botan::TLS::TLS_CBC_HMAC_AEAD_Mode.

Definition at line 244 of file cipher_mode.h.

244{ return 0; }

◆ update()

template<concepts::resizable_byte_buffer T>

void Botan::Cipher_Mode::update	(	T &	buffer,
		size_t	offset = `0`
	)

inlineinherited

Process some data. Input must be in size update_granularity() uint8_t blocks.

Parameters

buffer	in/out parameter which will possibly be resized
offset	an offset into blocks to begin processing

Definition at line 144 of file cipher_mode.h.

         {
         BOTAN_ASSERT(buffer.size() >= offset, "Offset ok");
         const size_t written = process(std::span(buffer).subspan(offset));
         buffer.resize(offset + written);
         }

References BOTAN_ASSERT.

Referenced by botan_cipher_update().

◆ update_granularity()

size_t Botan::CFB_Mode::update_granularity ( ) const

finaloverridevirtualinherited

Returns: size of required blocks to update

Implements Botan::Cipher_Mode.

Definition at line 51 of file cfb.cpp.

   {
   return feedback();
   }

References Botan::CFB_Mode::feedback().

◆ valid_keylength()

bool Botan::SymmetricAlgorithm::valid_keylength ( size_t length ) const

inlineinherited

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 141 of file sym_algo.h.

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

Referenced by Botan::SymmetricAlgorithm::set_key().

◆ valid_nonce_length()

bool Botan::CFB_Mode::valid_nonce_length ( size_t nonce_len ) const

finaloverridevirtualinherited

Returns: true iff nonce_len is a valid length for the nonce

Implements Botan::Cipher_Mode.

Definition at line 77 of file cfb.cpp.

   {
   return (n == 0 || n == block_size());
   }

References Botan::CFB_Mode::block_size().

Member Data Documentation

◆ m_keystream

secure_vector<uint8_t> Botan::CFB_Mode::m_keystream

protectedinherited

Definition at line 54 of file cfb.h.

Referenced by Botan::CFB_Mode::clear(), Botan::CFB_Mode::reset(), and Botan::CFB_Mode::shift_register().

◆ m_keystream_pos

size_t Botan::CFB_Mode::m_keystream_pos = 0

protectedinherited

Definition at line 55 of file cfb.h.

Referenced by Botan::CFB_Mode::shift_register().

◆ m_state

secure_vector<uint8_t> Botan::CFB_Mode::m_state

protectedinherited

Definition at line 53 of file cfb.h.

Referenced by Botan::CFB_Mode::reset(), and Botan::CFB_Mode::shift_register().

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

src/lib/modes/cfb/cfb.h
src/lib/modes/cfb/cfb.cpp

Public Member Functions

Static Public Member Functions

Protected Member Functions

Protected Attributes

Detailed Description

Constructor & Destructor Documentation

◆ CFB_Decryption()

Member Function Documentation

◆ assert_key_material_set() [1/2]

◆ assert_key_material_set() [2/2]

◆ authenticated()

◆ block_size()

◆ cipher()

◆ clear()

◆ create()

◆ create_or_throw()

◆ default_nonce_length()

◆ feedback()

◆ finish() [1/2]

◆ finish() [2/2]

◆ has_keying_material()

◆ ideal_granularity()

◆ key_spec()

◆ maximum_keylength()

◆ minimum_final_size()

◆ minimum_keylength()

◆ name()

◆ output_length()

◆ process() [1/2]

◆ process() [2/2]

◆ provider()

◆ providers()

◆ requires_entire_message()

◆ reset()

◆ set_key() [1/3]

◆ set_key() [2/3]

◆ set_key() [3/3]

◆ shift_register()

◆ start() [1/3]

◆ start() [2/3]

◆ start() [3/3]

◆ tag_size()

◆ update()

◆ update_granularity()

◆ valid_keylength()

◆ valid_nonce_length()

Member Data Documentation

◆ m_keystream

◆ m_keystream_pos

◆ m_state