Botan  1.11.10
Public Member Functions | Protected Member Functions | List of all members
Botan::ECB_Decryption Class Reference

#include <ecb.h>

Inheritance diagram for Botan::ECB_Decryption:
Botan::ECB_Mode Botan::Cipher_Mode Botan::Keyed_Transform Botan::Transformation

Public Member Functions

virtual bool authenticated () const
 
void clear () override
 
size_t default_nonce_length () const override
 
 ECB_Decryption (BlockCipher *cipher, BlockCipherModePaddingMethod *padding)
 
void finish (secure_vector< byte > &final_block, size_t offset=0) override
 
Key_Length_Specification key_spec () const override
 
size_t minimum_final_size () const override
 
std::string name () const override
 
size_t output_length (size_t input_length) const override
 
virtual std::string provider () const
 
template<typename Alloc >
void set_key (const std::vector< byte, Alloc > &key)
 
void set_key (const SymmetricKey &key)
 
void set_key (const byte key[], size_t length)
 
secure_vector< bytestart (const byte nonce[], size_t nonce_len) override
 
template<typename Alloc >
secure_vector< bytestart_vec (const std::vector< byte, Alloc > &nonce)
 
void update (secure_vector< byte > &blocks, size_t offset=0) override
 
size_t update_granularity () const override
 
bool valid_keylength (size_t length) const
 
bool valid_nonce_length (size_t n) const override
 

Protected Member Functions

const BlockCiphercipher () const
 
const
BlockCipherModePaddingMethod
padding () const
 

Detailed Description

ECB Decryption

Definition at line 71 of file ecb.h.

Constructor & Destructor Documentation

Botan::ECB_Decryption::ECB_Decryption ( BlockCipher cipher,
BlockCipherModePaddingMethod padding 
)
inline

Definition at line 74 of file ecb.h.

74  :
const BlockCipher & cipher() const
Definition: ecb.h:39
ECB_Mode(BlockCipher *cipher, BlockCipherModePaddingMethod *padding)
Definition: ecb.cpp:15
const BlockCipherModePaddingMethod & padding() const
Definition: ecb.h:41

Member Function Documentation

virtual bool Botan::Cipher_Mode::authenticated ( ) const
inlinevirtualinherited

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

Reimplemented in Botan::AEAD_Mode.

Definition at line 25 of file cipher_mode.h.

25 { return false; }
const BlockCipher& Botan::ECB_Mode::cipher ( ) const
inlineprotectedinherited
void Botan::ECB_Mode::clear ( )
overridevirtualinherited

Implements Botan::Transformation.

Definition at line 25 of file ecb.cpp.

26  {
27  m_cipher->clear();
28  }
size_t Botan::ECB_Mode::default_nonce_length ( ) const
overridevirtualinherited

Return the default size for a nonce

Implements Botan::Transformation.

Definition at line 45 of file ecb.cpp.

46  {
47  return 0;
48  }
void Botan::ECB_Decryption::finish ( secure_vector< byte > &  final_block,
size_t  offset = 0 
)
overridevirtual

Complete processing of a message.

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

Implements Botan::Transformation.

Definition at line 133 of file ecb.cpp.

References Botan::BlockCipher::block_size(), BOTAN_ASSERT, Botan::ECB_Mode::cipher(), Botan::ECB_Mode::name(), Botan::ECB_Mode::padding(), Botan::BlockCipherModePaddingMethod::unpad(), and update().

134  {
135  BOTAN_ASSERT(buffer.size() >= offset, "Offset is sane");
136  const size_t sz = buffer.size() - offset;
137 
138  const size_t BS = cipher().block_size();
139 
140  if(sz == 0 || sz % BS)
141  throw Decoding_Error(name() + ": Ciphertext not a multiple of block size");
142 
143  update(buffer, offset);
144 
145  const size_t pad_bytes = BS - padding().unpad(&buffer[buffer.size()-BS], BS);
146  buffer.resize(buffer.size() - pad_bytes); // remove padding
147  }
const BlockCipher & cipher() const
Definition: ecb.h:39
#define BOTAN_ASSERT(expr, assertion_made)
Definition: assert.h:27
const BlockCipherModePaddingMethod & padding() const
Definition: ecb.h:41
std::string name() const override
Definition: ecb.cpp:30
void update(secure_vector< byte > &blocks, size_t offset=0) override
Definition: ecb.cpp:119
virtual size_t block_size() const =0
virtual size_t unpad(const byte block[], size_t size) const =0
Key_Length_Specification Botan::ECB_Mode::key_spec ( ) const
overridevirtualinherited
Returns
object describing limits on key size

Implements Botan::Keyed_Transform.

Definition at line 40 of file ecb.cpp.

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

41  {
42  return cipher().key_spec();
43  }
const BlockCipher & cipher() const
Definition: ecb.h:39
virtual Key_Length_Specification key_spec() const =0
size_t Botan::ECB_Decryption::minimum_final_size ( ) const
overridevirtual
Returns
required minimium size to finalize() - may be any length larger than this.

Implements Botan::Transformation.

Definition at line 114 of file ecb.cpp.

References Botan::BlockCipher::block_size(), and Botan::ECB_Mode::cipher().

115  {
116  return cipher().block_size();
117  }
const BlockCipher & cipher() const
Definition: ecb.h:39
virtual size_t block_size() const =0
std::string Botan::ECB_Mode::name ( ) const
overridevirtualinherited

Implements Botan::Transformation.

Definition at line 30 of file ecb.cpp.

References Botan::ECB_Mode::cipher(), Botan::BlockCipherModePaddingMethod::name(), Botan::SymmetricAlgorithm::name(), and Botan::ECB_Mode::padding().

Referenced by Botan::ECB_Encryption::finish(), finish(), and Botan::ECB_Mode::start().

31  {
32  return cipher().name() + "/ECB/" + padding().name();
33  }
const BlockCipher & cipher() const
Definition: ecb.h:39
virtual std::string name() const =0
const BlockCipherModePaddingMethod & padding() const
Definition: ecb.h:41
virtual std::string name() const =0
size_t Botan::ECB_Decryption::output_length ( size_t  input_length) const
overridevirtual

Returns the size of the output if this transform is used to process a message with input_length bytes. Will throw if unable to give a precise answer.

Implements Botan::Transformation.

Definition at line 109 of file ecb.cpp.

110  {
111  return input_length;
112  }
const BlockCipherModePaddingMethod& Botan::ECB_Mode::padding ( ) const
inlineprotectedinherited

Definition at line 41 of file ecb.h.

Referenced by Botan::ECB_Encryption::finish(), finish(), and Botan::ECB_Mode::name().

41 { return *m_padding; }
virtual std::string Botan::Transformation::provider ( ) const
inlinevirtualinherited

Return some short name describing the provider of this tranformation. Useful in cases where multiple implementations are available (eg, different implementations of AES). Default "core" is used for the 'standard' implementation included in the library.

Definition at line 93 of file transform.h.

93 { return "core"; }
template<typename Alloc >
void Botan::Keyed_Transform::set_key ( const std::vector< byte, Alloc > &  key)
inlineinherited

Definition at line 121 of file transform.h.

122  {
123  set_key(&key[0], key.size());
124  }
void set_key(const std::vector< byte, Alloc > &key)
Definition: transform.h:121
void Botan::Keyed_Transform::set_key ( const SymmetricKey key)
inlineinherited

Definition at line 126 of file transform.h.

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

127  {
128  set_key(key.begin(), key.length());
129  }
void set_key(const std::vector< byte, Alloc > &key)
Definition: transform.h:121
void Botan::Keyed_Transform::set_key ( const byte  key[],
size_t  length 
)
inlineinherited

Set the symmetric key of this transform

Parameters
keycontains the key material
lengthin bytes of key param

Definition at line 136 of file transform.h.

137  {
138  if(!valid_keylength(length))
139  throw Invalid_Key_Length(name(), length);
140  key_schedule(key, length);
141  }
virtual std::string name() const =0
bool valid_keylength(size_t length) const
Definition: transform.h:115
secure_vector< byte > Botan::ECB_Mode::start ( const byte  nonce[],
size_t  nonce_len 
)
overridevirtualinherited

Begin processing a message.

Parameters
noncethe per message nonce
nonce_lenlength of nonce

Implements Botan::Transformation.

Definition at line 60 of file ecb.cpp.

References Botan::ECB_Mode::name(), and Botan::ECB_Mode::valid_nonce_length().

61  {
62  if(!valid_nonce_length(nonce_len))
63  throw Invalid_IV_Length(name(), nonce_len);
64 
65  return secure_vector<byte>();
66  }
bool valid_nonce_length(size_t n) const override
Definition: ecb.cpp:50
std::string name() const override
Definition: ecb.cpp:30
template<typename Alloc >
secure_vector<byte> Botan::Transformation::start_vec ( const std::vector< byte, Alloc > &  nonce)
inlineinherited

Begin processing a message.

Parameters
noncethe per message nonce

Definition at line 31 of file transform.h.

32  {
33  return start(&nonce[0], nonce.size());
34  }
virtual secure_vector< byte > start(const byte nonce[], size_t nonce_len)=0
void Botan::ECB_Decryption::update ( secure_vector< byte > &  blocks,
size_t  offset = 0 
)
overridevirtual

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

Parameters
blocksin/out paramter which will possibly be resized
offsetan offset into blocks to begin processing

Implements Botan::Transformation.

Definition at line 119 of file ecb.cpp.

References Botan::BlockCipher::block_size(), BOTAN_ASSERT, Botan::ECB_Mode::cipher(), and Botan::BlockCipher::decrypt_n().

Referenced by finish().

120  {
121  BOTAN_ASSERT(buffer.size() >= offset, "Offset is sane");
122  const size_t sz = buffer.size() - offset;
123  byte* buf = &buffer[offset];
124 
125  const size_t BS = cipher().block_size();
126 
127  BOTAN_ASSERT(sz % BS == 0, "Input is full blocks");
128  size_t blocks = sz / BS;
129 
130  cipher().decrypt_n(&buf[0], &buf[0], blocks);
131  }
const BlockCipher & cipher() const
Definition: ecb.h:39
#define BOTAN_ASSERT(expr, assertion_made)
Definition: assert.h:27
uint8_t byte
Definition: types.h:30
virtual void decrypt_n(const byte in[], byte out[], size_t blocks) const =0
virtual size_t block_size() const =0
size_t Botan::ECB_Mode::update_granularity ( ) const
overridevirtualinherited
Returns
size of required blocks to update

Implements Botan::Transformation.

Definition at line 35 of file ecb.cpp.

References Botan::ECB_Mode::cipher(), and Botan::BlockCipher::parallel_bytes().

36  {
37  return cipher().parallel_bytes();
38  }
const BlockCipher & cipher() const
Definition: ecb.h:39
size_t parallel_bytes() const
Definition: block_cipher.h:35
bool Botan::Keyed_Transform::valid_keylength ( size_t  length) const
inlineinherited

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

Parameters
lengththe key length to be checked.
Returns
true if the key length is valid.

Definition at line 115 of file transform.h.

116  {
117  return key_spec().valid_keylength(length);
118  }
bool valid_keylength(size_t length) const
Definition: key_spec.h:51
virtual Key_Length_Specification key_spec() const =0
bool Botan::ECB_Mode::valid_nonce_length ( size_t  nonce_len) const
overridevirtualinherited

Return true iff nonce_len is a valid length for the nonce

Implements Botan::Transformation.

Definition at line 50 of file ecb.cpp.

Referenced by Botan::ECB_Mode::start().

51  {
52  return (n == 0);
53  }

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