Botan  1.10.9
Public Member Functions | Protected Member Functions | List of all members
Botan::CFB_Decryption Class Reference

#include <cfb.h>

Inheritance diagram for Botan::CFB_Decryption:
Botan::Keyed_Filter Botan::Filter

Public Member Functions

virtual bool attachable ()
 
 CFB_Decryption (BlockCipher *cipher, size_t feedback=0)
 
 CFB_Decryption (BlockCipher *cipher, const SymmetricKey &key, const InitializationVector &iv, size_t feedback=0)
 
virtual void end_msg ()
 
std::string name () const
 
void set_iv (const InitializationVector &)
 
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
 
 ~CFB_Decryption ()
 

Protected Member Functions

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

Detailed Description

CFB Decryption

Definition at line 53 of file cfb.h.

Constructor & Destructor Documentation

Botan::CFB_Decryption::CFB_Decryption ( BlockCipher cipher,
size_t  feedback = 0 
)

Definition at line 95 of file cfb.cpp.

References Botan::BlockCipher::block_size(), Botan::MemoryRegion< T >::resize(), and Botan::to_string().

96  {
97  cipher = ciph;
98  feedback = fback_bits ? fback_bits / 8: cipher->block_size();
99 
100  buffer.resize(cipher->block_size());
101  state.resize(cipher->block_size());
102  position = 0;
103 
104  if(feedback == 0 || fback_bits % 8 != 0 || feedback > cipher->block_size())
105  throw Invalid_Argument("CFB_Decryption: Invalid feedback size " +
106  to_string(fback_bits));
107  }
void resize(size_t n)
Definition: secmem.h:211
std::invalid_argument Invalid_Argument
Definition: exceptn.h:20
std::string to_string(u64bit n, size_t min_len)
Definition: parsing.cpp:42
virtual size_t block_size() const =0
Botan::CFB_Decryption::CFB_Decryption ( BlockCipher cipher,
const SymmetricKey key,
const InitializationVector iv,
size_t  feedback = 0 
)

Definition at line 112 of file cfb.cpp.

References Botan::BlockCipher::block_size(), Botan::MemoryRegion< T >::resize(), set_iv(), set_key(), and Botan::to_string().

116  {
117  cipher = ciph;
118  feedback = fback_bits ? fback_bits / 8: cipher->block_size();
119 
120  buffer.resize(cipher->block_size());
121  state.resize(cipher->block_size());
122  position = 0;
123 
124  if(feedback == 0 || fback_bits % 8 != 0 || feedback > cipher->block_size())
125  throw Invalid_Argument("CFB_Decryption: Invalid feedback size " +
126  to_string(fback_bits));
127 
128  set_key(key);
129  set_iv(iv);
130  }
void resize(size_t n)
Definition: secmem.h:211
void set_key(const SymmetricKey &key)
Definition: cfb.h:60
std::invalid_argument Invalid_Argument
Definition: exceptn.h:20
void set_iv(const InitializationVector &)
Definition: cfb.cpp:132
std::string to_string(u64bit n, size_t min_len)
Definition: parsing.cpp:42
virtual size_t block_size() const =0
Botan::CFB_Decryption::~CFB_Decryption ( )
inline

Definition at line 75 of file cfb.h.

75 { delete cipher; }

Member Function Documentation

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::SecureQueue, and Botan::DataSink.

Definition at line 50 of file filter.h.

50 { return true; }
virtual void Botan::Filter::end_msg ( )
inlinevirtualinherited
std::string Botan::CFB_Decryption::name ( ) const
inlinevirtual
Returns
descriptive name for this filter

Implements Botan::Filter.

Definition at line 56 of file cfb.h.

Referenced by set_iv().

56 { return cipher->name() + "/CFB"; }
virtual std::string name() const =0
void Botan::Filter::send ( const byte  in[],
size_t  length 
)
protectedinherited
Parameters
insome input for the filter
lengththe length of in

Definition at line 28 of file filter.cpp.

References Botan::MemoryRegion< T >::clear(), Botan::MemoryRegion< T >::size(), and Botan::Filter::write().

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

29  {
30  bool nothing_attached = true;
31  for(size_t j = 0; j != total_ports(); ++j)
32  if(next[j])
33  {
34  if(write_queue.size())
35  next[j]->write(&write_queue[0], write_queue.size());
36  next[j]->write(input, length);
37  nothing_attached = false;
38  }
39 
40  if(nothing_attached)
41  write_queue += std::make_pair(input, length);
42  else
43  write_queue.clear();
44  }
virtual void write(const byte input[], size_t length)=0
size_t size() const
Definition: secmem.h:29
void Botan::Filter::send ( byte  in)
inlineprotectedinherited
Parameters
insome input for the filter

Definition at line 63 of file filter.h.

References Botan::Filter::send().

Referenced by Botan::Filter::send().

63 { send(&in, 1); }
void send(const byte in[], size_t length)
Definition: filter.cpp:28
void Botan::Filter::send ( const MemoryRegion< byte > &  in)
inlineprotectedinherited
Parameters
insome input for the filter

Definition at line 68 of file filter.h.

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

Referenced by Botan::Filter::send().

68 { send(&in[0], in.size()); }
void send(const byte in[], size_t length)
Definition: filter.cpp:28
size_t size() const
Definition: secmem.h:29
void Botan::Filter::send ( const MemoryRegion< byte > &  in,
size_t  length 
)
inlineprotectedinherited
Parameters
insome input for the filter
lengththe number of bytes of in to send

Definition at line 74 of file filter.h.

75  {
76  send(&in[0], length);
77  }
void send(const byte in[], size_t length)
Definition: filter.cpp:28
void Botan::CFB_Decryption::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
ivthe initialization vector to use

Reimplemented from Botan::Keyed_Filter.

Definition at line 132 of file cfb.cpp.

References Botan::OctetString::bits_of(), Botan::BlockCipher::encrypt(), Botan::OctetString::length(), name(), valid_iv_length(), and Botan::zeroise().

Referenced by CFB_Decryption().

133  {
134  if(!valid_iv_length(iv.length()))
135  throw Invalid_IV_Length(name(), iv.length());
136 
137  state = iv.bits_of();
138  zeroise(buffer);
139  position = 0;
140 
141  cipher->encrypt(state, buffer);
142  }
std::string name() const
Definition: cfb.h:56
void encrypt(const byte in[], byte out[]) const
Definition: block_cipher.h:47
bool valid_iv_length(size_t iv_len) const
Definition: cfb.h:65
void zeroise(MemoryRegion< T > &vec)
Definition: secmem.h:415
void Botan::CFB_Decryption::set_key ( const SymmetricKey key)
inlinevirtual

Set the key of this filter

Parameters
keythe key to use

Implements Botan::Keyed_Filter.

Definition at line 60 of file cfb.h.

Referenced by CFB_Decryption().

60 { cipher->set_key(key); }
void set_key(const SymmetricKey &key)
Definition: sym_algo.h:60
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::Zlib_Decompression, Botan::EAX_Base, Botan::Bzip_Decompression, Botan::PBE_PKCS5v20, Botan::PBE_PKCS5v15, Botan::Bzip_Compression, and Botan::Zlib_Compression.

Definition at line 38 of file filter.h.

38 {}
bool Botan::CFB_Decryption::valid_iv_length ( size_t  length) const
inlinevirtual

Check whether an IV length is valid for this filter

Parameters
lengththe 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 65 of file cfb.h.

Referenced by set_iv().

66  { return (iv_len == cipher->block_size()); }
virtual size_t block_size() const =0
bool Botan::CFB_Decryption::valid_keylength ( size_t  length) const
inlinevirtual

Check whether a key length is valid for this filter

Parameters
lengththe key length to be checked for validity
Returns
true if the key length is valid, false otherwise

Implements Botan::Keyed_Filter.

Definition at line 62 of file cfb.h.

63  { return cipher->valid_keylength(key_len); }
bool valid_keylength(size_t length) const
Definition: sym_algo.h:51

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