Botan  1.11.15
Public Types | 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::Transform

Public Types

typedef SCAN_Name Spec
 

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)
 
template<typename Alloc >
secure_vector< bytestart (const std::vector< byte, Alloc > &nonce)
 
secure_vector< bytestart (const byte nonce[], size_t nonce_len)
 
secure_vector< bytestart ()
 
template<typename Alloc >
secure_vector< bytestart_vec (const std::vector< byte, Alloc > &nonce)
 
virtual size_t tag_size () const
 
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 BlockCipherModePaddingMethodpadding () const
 

Detailed Description

ECB Decryption

Definition at line 70 of file ecb.h.

Member Typedef Documentation

typedef SCAN_Name Botan::Transform::Spec
inherited

Definition at line 27 of file transform.h.

Constructor & Destructor Documentation

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

Definition at line 73 of file ecb.h.

73  :
const BlockCipher & cipher() const
Definition: ecb.h:37
ECB_Mode(BlockCipher *cipher, BlockCipherModePaddingMethod *padding)
Definition: ecb.cpp:26
const BlockCipherModePaddingMethod & padding() const
Definition: ecb.h:39

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 26 of file cipher_mode.h.

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

Implements Botan::Transform.

Definition at line 36 of file ecb.cpp.

37  {
38  m_cipher->clear();
39  }
size_t Botan::ECB_Mode::default_nonce_length ( ) const
overridevirtualinherited

Return the default size for a nonce

Implements Botan::Transform.

Definition at line 56 of file ecb.cpp.

57  {
58  return 0;
59  }
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::Transform.

Definition at line 144 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().

145  {
146  BOTAN_ASSERT(buffer.size() >= offset, "Offset is sane");
147  const size_t sz = buffer.size() - offset;
148 
149  const size_t BS = cipher().block_size();
150 
151  if(sz == 0 || sz % BS)
152  throw Decoding_Error(name() + ": Ciphertext not a multiple of block size");
153 
154  update(buffer, offset);
155 
156  const size_t pad_bytes = BS - padding().unpad(&buffer[buffer.size()-BS], BS);
157  buffer.resize(buffer.size() - pad_bytes); // remove padding
158  }
const BlockCipher & cipher() const
Definition: ecb.h:37
#define BOTAN_ASSERT(expr, assertion_made)
Definition: assert.h:27
const BlockCipherModePaddingMethod & padding() const
Definition: ecb.h:39
std::string name() const override
Definition: ecb.cpp:41
void update(secure_vector< byte > &blocks, size_t offset=0) override
Definition: ecb.cpp:130
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 51 of file ecb.cpp.

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

52  {
53  return cipher().key_spec();
54  }
const BlockCipher & cipher() const
Definition: ecb.h:37
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::Transform.

Definition at line 125 of file ecb.cpp.

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

126  {
127  return cipher().block_size();
128  }
const BlockCipher & cipher() const
Definition: ecb.h:37
virtual size_t block_size() const =0
std::string Botan::ECB_Mode::name ( ) const
overridevirtualinherited

Implements Botan::Transform.

Definition at line 41 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(), and finish().

42  {
43  return cipher().name() + "/ECB/" + padding().name();
44  }
const BlockCipher & cipher() const
Definition: ecb.h:37
virtual std::string name() const =0
const BlockCipherModePaddingMethod & padding() const
Definition: ecb.h:39
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::Transform.

Definition at line 120 of file ecb.cpp.

121  {
122  return input_length;
123  }
const BlockCipherModePaddingMethod& Botan::ECB_Mode::padding ( ) const
inlineprotectedinherited

Definition at line 39 of file ecb.h.

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

39 { return *m_padding; }
virtual std::string Botan::Transform::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 120 of file transform.h.

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

Definition at line 148 of file transform.h.

Referenced by botan_cipher_set_key().

149  {
150  set_key(&key[0], key.size());
151  }
void set_key(const std::vector< byte, Alloc > &key)
Definition: transform.h:148
void Botan::Keyed_Transform::set_key ( const SymmetricKey key)
inlineinherited

Definition at line 153 of file transform.h.

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

154  {
155  set_key(key.begin(), key.length());
156  }
void set_key(const std::vector< byte, Alloc > &key)
Definition: transform.h:148
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 163 of file transform.h.

164  {
165  if(!valid_keylength(length))
166  throw Invalid_Key_Length(name(), length);
167  key_schedule(key, length);
168  }
virtual std::string name() const =0
bool valid_keylength(size_t length) const
Definition: transform.h:142
template<typename Alloc >
secure_vector<byte> Botan::Transform::start ( const std::vector< byte, Alloc > &  nonce)
inlineinherited

Begin processing a message.

Parameters
noncethe per message nonce

Definition at line 34 of file transform.h.

Referenced by botan_cipher_start().

35  {
36  return start(&nonce[0], nonce.size());
37  }
secure_vector< byte > start()
Definition: transform.h:63
secure_vector<byte> Botan::Transform::start ( const byte  nonce[],
size_t  nonce_len 
)
inlineinherited

Begin processing a message.

Parameters
noncethe per message nonce
nonce_lenlength of nonce

Definition at line 55 of file transform.h.

56  {
57  return start_raw(nonce, nonce_len);
58  }
virtual secure_vector< byte > start_raw(const byte nonce[], size_t nonce_len)=0
secure_vector<byte> Botan::Transform::start ( )
inlineinherited

Begin processing a message.

Definition at line 63 of file transform.h.

64  {
65  return start_raw(nullptr, 0);
66  }
virtual secure_vector< byte > start_raw(const byte nonce[], size_t nonce_len)=0
template<typename Alloc >
secure_vector<byte> Botan::Transform::start_vec ( const std::vector< byte, Alloc > &  nonce)
inlineinherited

Begin processing a message.

Parameters
noncethe per message nonce

Definition at line 45 of file transform.h.

46  {
47  return start(&nonce[0], nonce.size());
48  }
secure_vector< byte > start()
Definition: transform.h:63
virtual size_t Botan::Cipher_Mode::tag_size ( ) const
inlinevirtualinherited

Return the size of the authentication tag used (in bytes)

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

Definition at line 31 of file cipher_mode.h.

Referenced by botan_cipher_get_tag_length().

31 { return 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::Transform.

Definition at line 130 of file ecb.cpp.

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

Referenced by finish().

131  {
132  BOTAN_ASSERT(buffer.size() >= offset, "Offset is sane");
133  const size_t sz = buffer.size() - offset;
134  byte* buf = &buffer[offset];
135 
136  const size_t BS = cipher().block_size();
137 
138  BOTAN_ASSERT(sz % BS == 0, "Input is full blocks");
139  size_t blocks = sz / BS;
140 
141  cipher().decrypt_n(&buf[0], &buf[0], blocks);
142  }
const BlockCipher & cipher() const
Definition: ecb.h:37
#define BOTAN_ASSERT(expr, assertion_made)
Definition: assert.h:27
uint8_t byte
Definition: types.h:31
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::Transform.

Definition at line 46 of file ecb.cpp.

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

47  {
48  return cipher().parallel_bytes();
49  }
const BlockCipher & cipher() const
Definition: ecb.h:37
size_t parallel_bytes() const
Definition: block_cipher.h:37
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 142 of file transform.h.

143  {
144  return key_spec().valid_keylength(length);
145  }
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::Transform.

Definition at line 61 of file ecb.cpp.

62  {
63  return (n == 0);
64  }
const BigInt & n
Definition: rsa.cpp:107

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