Botan::XTS_Encryption Class Reference

#include <xts.h>

Inheritance diagram for Botan::XTS_Encryption:

Public Member Functions
virtual bool	attachable ()
std::string	name () const
void	set_iv (const InitializationVector &iv)
void	set_key (const SymmetricKey &key)
virtual void	start_msg ()
bool	valid_iv_length (size_t iv_len) const
bool	valid_keylength (size_t key_len) const
	XTS_Encryption (BlockCipher *ciph)
	XTS_Encryption (BlockCipher *ciph, const SymmetricKey &key, const InitializationVector &iv)
	~XTS_Encryption ()

Protected Member Functions
void	send (byte in)
void	send (const byte in[], size_t length)
void	send (const MemoryRegion< byte > &in)
void	send (const MemoryRegion< byte > &in, size_t length)

Detailed Description

IEEE P1619 XTS Encryption

Definition at line 20 of file xts.h.

Constructor & Destructor Documentation

XTS_Encryption() [1/2]

Botan::XTS_Encryption::XTS_Encryption

(

BlockCipher *

ciph

)

Definition at line 47 of file xts.cpp.

                                                :
   Buffered_Filter(xts_parallelism(ciph), ciph->block_size() + 1),
   cipher(ciph)
   {
   if(cipher->block_size() != 8 && cipher->block_size() != 16)
      throw std::invalid_argument("Bad cipher for XTS: " + cipher->name());
 
   cipher2 = cipher->clone();
   tweak.resize(buffered_block_size());
   }

References Botan::Buffered_Filter::buffered_block_size(), and Botan::Buffered_Filter::Buffered_Filter().

Referenced by Botan::get_cipher_mode().

XTS_Encryption() [2/2]

Botan::XTS_Encryption::XTS_Encryption	(	BlockCipher *	ciph,
		const SymmetricKey &	key,
		const InitializationVector &	iv )

Definition at line 61 of file xts.cpp.

                                                               :
   Buffered_Filter(xts_parallelism(ciph), ciph->block_size() + 1),
   cipher(ciph)
   {
   if(cipher->block_size() != 8 && cipher->block_size() != 16)
       throw std::invalid_argument("Bad cipher for XTS: " + cipher->name());
 
   cipher2 = cipher->clone();
   tweak.resize(buffered_block_size());
 
   set_key(key);
   set_iv(iv);
   }

References Botan::Buffered_Filter::buffered_block_size(), Botan::Buffered_Filter::Buffered_Filter(), set_iv(), and set_key().

~XTS_Encryption()

Botan::XTS_Encryption::~XTS_Encryption ( )

inline

Definition at line 41 of file xts.h.

{ delete cipher; delete cipher2; }

Member Function Documentation

attachable()

virtual bool Botan::Filter::attachable ( )

inlinevirtualinherited

Check whether this filter is an attachable filter.

Returns

true if this filter is attachable, false otherwise

Reimplemented in Botan::DataSink, and Botan::SecureQueue.

Definition at line 50 of file filter.h.

{ return true; }

name()

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

virtual

Returns

descriptive name for this filter

Implements Botan::Filter.

Definition at line 80 of file xts.cpp.

   {
   return (cipher->name() + "/XTS");
   }

Referenced by set_iv(), and set_key().

send() [1/4]

void Botan::Filter::send ( byte in )

inlineprotectedinherited

Parameters

in	some input for the filter

Definition at line 63 of file filter.h.

{ send(&in, 1); }

References send().

Referenced by send().

send() [2/4]

void Botan::Filter::send ( const byte in[], size_t length )

protectedinherited

Parameters

in	some input for the filter
length	the length of in

Definition at line 28 of file filter.cpp.

   {
   bool nothing_attached = true;
   for(size_t j = 0; j != total_ports(); ++j)
      if(next[j])
         {
         if(write_queue.size())
            next[j]->write(&write_queue[0], write_queue.size());
         next[j]->write(input, length);
         nothing_attached = false;
         }
 
   if(nothing_attached)
      write_queue += std::make_pair(input, length);
   else
      write_queue.clear();
   }

Referenced by Botan::Base64_Decoder::end_msg(), Botan::Base64_Encoder::end_msg(), Botan::Bzip_Compression::end_msg(), Botan::Bzip_Decompression::end_msg(), Botan::Hash_Filter::end_msg(), Botan::Hex_Decoder::end_msg(), Botan::Hex_Encoder::end_msg(), Botan::MAC_Filter::end_msg(), Botan::PK_Decryptor_Filter::end_msg(), Botan::PK_Encryptor_Filter::end_msg(), Botan::PK_Signer_Filter::end_msg(), Botan::PK_Verifier_Filter::end_msg(), Botan::Zlib_Compression::end_msg(), Botan::Zlib_Decompression::end_msg(), Botan::Bzip_Compression::flush(), Botan::Zlib_Compression::flush(), send(), Botan::Base64_Decoder::write(), Botan::Bzip_Compression::write(), Botan::Bzip_Decompression::write(), Botan::Chain::write(), Botan::Fork::write(), Botan::Hex_Decoder::write(), Botan::StreamCipher_Filter::write(), Botan::Zlib_Compression::write(), and Botan::Zlib_Decompression::write().

send() [3/4]

void Botan::Filter::send ( const MemoryRegion< byte > & in )

inlineprotectedinherited

Parameters

in	some input for the filter

Definition at line 68 of file filter.h.

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

References send(), and Botan::MemoryRegion< T >::size().

Referenced by send().

send() [4/4]

void Botan::Filter::send ( const MemoryRegion< byte > & in, size_t length )

inlineprotectedinherited

Parameters

in	some input for the filter
length	the number of bytes of in to send

Definition at line 74 of file filter.h.

         {
         send(&in[0], length);
         }

References send().

set_iv()

void Botan::XTS_Encryption::set_iv ( const InitializationVector & iv )

virtual

Set the initialization vector of this filter. Note: you should call set_iv() only after you have called set_key()

Parameters

iv	the initialization vector to use

Reimplemented from Botan::Keyed_Filter.

Definition at line 88 of file xts.cpp.

   {
   if(!valid_iv_length(iv.length()))
      throw Invalid_IV_Length(name(), iv.length());
 
   const size_t blocks_in_tweak = tweak.size() / cipher->block_size();
 
   tweak.copy(iv.begin(), iv.length());
   cipher2->encrypt(tweak);
 
   for(size_t i = 1; i < blocks_in_tweak; ++i)
      {
      tweak.copy(i*cipher->block_size(),
                 &tweak[(i-1)*cipher->block_size()],
                 cipher->block_size());
 
      poly_double(&tweak[i*cipher->block_size()], cipher->block_size());
      }
   }

References Botan::OctetString::begin(), Botan::Invalid_IV_Length::Invalid_IV_Length(), Botan::OctetString::length(), name(), and valid_iv_length().

Referenced by XTS_Encryption().

set_key()

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

virtual

Set the key of this filter

Parameters

key	the key to use

Implements Botan::Keyed_Filter.

Definition at line 108 of file xts.cpp.

   {
   size_t key_half = key.length() / 2;
 
   if(key.length() % 2 == 1 || !cipher->valid_keylength(key_half))
      throw Invalid_Key_Length(name(), key.length());
 
   cipher->set_key(key.begin(), key_half);
   cipher2->set_key(key.begin() + key_half, key_half);
   }

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

Referenced by XTS_Encryption().

start_msg()

virtual void Botan::Filter::start_msg ( )

inlinevirtualinherited

Start a new message. Must be closed by end_msg() before another message can be started.

Reimplemented in Botan::Bzip_Compression, Botan::Bzip_Decompression, Botan::EAX_Base, Botan::PBE_PKCS5v15, Botan::PBE_PKCS5v20, Botan::Zlib_Compression, and Botan::Zlib_Decompression.

Definition at line 38 of file filter.h.

{}

valid_iv_length()

bool Botan::XTS_Encryption::valid_iv_length ( size_t length ) const

inlinevirtual

Check whether an IV length is valid for this filter

Parameters

length

the IV length to be checked for validity

Returns

true if the IV length is valid, false otherwise

Reimplemented from Botan::Keyed_Filter.

Definition at line 30 of file xts.h.

         { return (iv_len == cipher->block_size()); }

Referenced by set_iv().

valid_keylength()

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

inlinevirtual

Check whether a key length is valid for this filter

Parameters

length

the key length to be checked for validity

Returns

true if the key length is valid, false otherwise

Implements Botan::Keyed_Filter.

Definition at line 27 of file xts.h.

         { return cipher->valid_keylength(key_len); }

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

• src/filters/modes/xts/xts.h
• src/filters/modes/xts/xts.cpp