Botan 1.10.17
Botan::CFB_Encryption Class Reference

#include <cfb.h>

Inheritance diagram for Botan::CFB_Encryption:
Botan::Keyed_Filter Botan::Filter

Public Member Functions

virtual bool attachable ()
 CFB_Encryption (BlockCipher *cipher, const SymmetricKey &key, const InitializationVector &iv, size_t feedback=0)
 CFB_Encryption (BlockCipher *cipher, 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_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

CFB Encryption

Definition at line 19 of file cfb.h.

Constructor & Destructor Documentation

◆ CFB_Encryption() [1/2]

Botan::CFB_Encryption::CFB_Encryption ( BlockCipher * cipher,
size_t feedback = 0 )

Definition at line 18 of file cfb.cpp.

19 {
20 cipher = ciph;
21 feedback = fback_bits ? fback_bits / 8: cipher->block_size();
22
23 buffer.resize(cipher->block_size());
24 state.resize(cipher->block_size());
25 position = 0;
26
27 if(feedback == 0 || fback_bits % 8 != 0 || feedback > cipher->block_size())
28 throw Invalid_Argument("CFB_Encryption: Invalid feedback size " +
29 to_string(fback_bits));
30 }
std::string to_string(u64bit n, size_t min_len)
Definition parsing.cpp:42
std::invalid_argument Invalid_Argument
Definition exceptn.h:20

References Botan::BlockCipher::block_size(), and Botan::to_string().

Referenced by Botan::get_cipher_mode().

◆ CFB_Encryption() [2/2]

Botan::CFB_Encryption::CFB_Encryption ( BlockCipher * cipher,
const SymmetricKey & key,
const InitializationVector & iv,
size_t feedback = 0 )

Definition at line 35 of file cfb.cpp.

39 {
40 cipher = ciph;
41 feedback = fback_bits ? fback_bits / 8: cipher->block_size();
42
43 buffer.resize(cipher->block_size());
44 state.resize(cipher->block_size());
45 position = 0;
46
47 if(feedback == 0 || fback_bits % 8 != 0 || feedback > cipher->block_size())
48 throw Invalid_Argument("CFB_Encryption: Invalid feedback size " +
49 to_string(fback_bits));
50
51 set_key(key);
52 set_iv(iv);
53 }
void set_key(const SymmetricKey &key)
Definition cfb.h:26
void set_iv(const InitializationVector &)
Definition cfb.cpp:55

References Botan::BlockCipher::block_size(), set_iv(), set_key(), and Botan::to_string().

◆ ~CFB_Encryption()

Botan::CFB_Encryption::~CFB_Encryption ( )
inline

Definition at line 41 of file cfb.h.

41{ delete cipher; }

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.

50{ return true; }

◆ end_msg()

virtual void Botan::Filter::end_msg ( )
inlinevirtualinherited

◆ name()

std::string Botan::CFB_Encryption::name ( ) const
inlinevirtual
Returns
descriptive name for this filter

Implements Botan::Filter.

Definition at line 22 of file cfb.h.

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

Referenced by set_iv().

◆ send() [1/4]

void Botan::Filter::send ( byte in)
inlineprotectedinherited
Parameters
insome input for the filter

Definition at line 63 of file filter.h.

63{ send(&in, 1); }
void send(const byte in[], size_t length)
Definition filter.cpp:28

References send().

Referenced by send().

◆ send() [2/4]

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

◆ send() [3/4]

void Botan::Filter::send ( const MemoryRegion< byte > & in)
inlineprotectedinherited
Parameters
insome input for the filter

Definition at line 68 of file filter.h.

68{ 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
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 }

References send().

◆ set_iv()

void Botan::CFB_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
ivthe initialization vector to use

Reimplemented from Botan::Keyed_Filter.

Definition at line 55 of file cfb.cpp.

56 {
57 if(!valid_iv_length(iv.length()))
58 throw Invalid_IV_Length(name(), iv.length());
59
60 state = iv.bits_of();
61 zeroise(buffer);
62 position = 0;
63
64 cipher->encrypt(state, buffer);
65 }
std::string name() const
Definition cfb.h:22
bool valid_iv_length(size_t iv_len) const
Definition cfb.h:31
void zeroise(MemoryRegion< T > &vec)
Definition secmem.h:428
Invalid_IV_Length(const std::string &mode, size_t bad_len)
Definition exceptn.h:80

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

Referenced by CFB_Encryption().

◆ set_key()

void Botan::CFB_Encryption::set_key ( const SymmetricKey & key)
inlinevirtual

Set the key of this filter

Parameters
keythe key to use

Implements Botan::Keyed_Filter.

Definition at line 26 of file cfb.h.

26{ cipher->set_key(key); }

Referenced by CFB_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.

38{}

◆ valid_iv_length()

bool Botan::CFB_Encryption::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 31 of file cfb.h.

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

Referenced by set_iv().

◆ valid_keylength()

bool Botan::CFB_Encryption::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 28 of file cfb.h.

29 { return cipher->valid_keylength(key_len); }

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