Botan  2.10.0
Crypto and TLS for C++11
Public Member Functions | Static Public Member Functions | Protected Member Functions | Protected Attributes | List of all members
Botan::OCB_Mode Class Referenceabstract

#include <ocb.h>

Inheritance diagram for Botan::OCB_Mode:
Botan::AEAD_Mode Botan::Cipher_Mode Botan::SymmetricAlgorithm Botan::OCB_Decryption Botan::OCB_Encryption

Public Member Functions

virtual bool associated_data_requires_key () const
 
bool authenticated () const override
 
void clear () override
 
size_t default_nonce_length () const override
 
virtual void finish (secure_vector< uint8_t > &final_block, size_t offset=0)=0
 
Key_Length_Specification key_spec () const override
 
size_t maximum_keylength () const
 
virtual size_t minimum_final_size () const =0
 
size_t minimum_keylength () const
 
std::string name () const override
 
virtual size_t output_length (size_t input_length) const =0
 
virtual size_t process (uint8_t msg[], size_t msg_len)=0
 
virtual std::string provider () const
 
void reset () override
 
template<typename Alloc >
void set_ad (const std::vector< uint8_t, Alloc > &ad)
 
void set_associated_data (const uint8_t ad[], size_t ad_len) override
 
template<typename Alloc >
void set_associated_data_vec (const std::vector< uint8_t, Alloc > &ad)
 
void set_key (const SymmetricKey &key)
 
template<typename Alloc >
void set_key (const std::vector< uint8_t, Alloc > &key)
 
void set_key (const uint8_t key[], size_t length)
 
template<typename Alloc >
void start (const std::vector< uint8_t, Alloc > &nonce)
 
void start (const uint8_t nonce[], size_t nonce_len)
 
void start ()
 
size_t tag_size () const override
 
void update (secure_vector< uint8_t > &buffer, size_t offset=0)
 
size_t update_granularity () const override
 
bool valid_keylength (size_t length) const
 
bool valid_nonce_length (size_t) const override
 
 ~OCB_Mode ()
 

Static Public Member Functions

static std::unique_ptr< AEAD_Modecreate (const std::string &algo, Cipher_Dir direction, const std::string &provider="")
 
static std::unique_ptr< AEAD_Modecreate_or_throw (const std::string &algo, Cipher_Dir direction, const std::string &provider="")
 
static std::vector< std::string > providers (const std::string &algo_spec)
 

Protected Member Functions

size_t block_size () const
 
 OCB_Mode (BlockCipher *cipher, size_t tag_size)
 
size_t par_blocks () const
 
size_t par_bytes () const
 
void verify_key_set (bool cond) const
 

Protected Attributes

secure_vector< uint8_t > m_ad_hash
 
size_t m_block_index = 0
 
secure_vector< uint8_t > m_checksum
 
std::unique_ptr< BlockCipherm_cipher
 
std::unique_ptr< L_computer > m_L
 

Detailed Description

OCB Mode (base class for OCB_Encryption and OCB_Decryption). Note that OCB is patented, but is freely licensed in some circumstances.

See also
"The OCB Authenticated-Encryption Algorithm" RFC 7253 https://tools.ietf.org/html/rfc7253
"OCB For Block Ciphers Without 128-Bit Blocks" (draft-krovetz-ocb-wide-d3) for the extension of OCB to block ciphers with larger block sizes.
Free Licenses http://www.cs.ucdavis.edu/~rogaway/ocb/license.htm
OCB home page http://www.cs.ucdavis.edu/~rogaway/ocb

Definition at line 31 of file ocb.h.

Constructor & Destructor Documentation

◆ ~OCB_Mode()

Botan::OCB_Mode::~OCB_Mode ( )

Definition at line 185 of file ocb.cpp.

185 { /* for unique_ptr destructor */ }

◆ OCB_Mode()

Botan::OCB_Mode::OCB_Mode ( BlockCipher cipher,
size_t  tag_size 
)
protected
Parameters
cipherthe block cipher to use
tag_sizeis how big the auth tag will be

Definition at line 161 of file ocb.cpp.

161  :
162  m_cipher(cipher),
163  m_checksum(m_cipher->parallel_bytes()),
164  m_ad_hash(m_cipher->block_size()),
165  m_tag_size(tag_size),
166  m_block_size(m_cipher->block_size()),
167  m_par_blocks(m_cipher->parallel_bytes() / m_block_size)
168  {
169  const size_t BS = block_size();
170 
171  /*
172  * draft-krovetz-ocb-wide-d1 specifies OCB for several other block
173  * sizes but only 128, 192, 256 and 512 bit are currently supported
174  * by this implementation.
175  */
176  BOTAN_ARG_CHECK(BS == 16 || BS == 24 || BS == 32 || BS == 64,
177  "Invalid block size for OCB");
178 
179  BOTAN_ARG_CHECK(m_tag_size % 4 == 0 &&
180  m_tag_size >= 8 && m_tag_size <= BS &&
181  m_tag_size <= 32,
182  "Invalid OCB tag length");
183  }
std::unique_ptr< BlockCipher > m_cipher
Definition: ocb.h:63
size_t tag_size() const override
Definition: ocb.h:44
#define BOTAN_ARG_CHECK(expr, msg)
Definition: assert.h:37
size_t block_size() const
Definition: ocb.h:58
secure_vector< uint8_t > m_ad_hash
Definition: ocb.h:69
secure_vector< uint8_t > m_checksum
Definition: ocb.h:68

Member Function Documentation

◆ associated_data_requires_key()

virtual bool Botan::AEAD_Mode::associated_data_requires_key ( ) const
inlinevirtualinherited

Most AEADs require the key to be set prior to setting the AD A few allow the AD to be set even before the cipher is keyed. Such ciphers would return false from this function.

Reimplemented in Botan::ChaCha20Poly1305_Mode, and Botan::CCM_Mode.

Definition at line 68 of file aead.h.

68 { return true; }

◆ authenticated()

bool Botan::AEAD_Mode::authenticated ( ) const
inlineoverridevirtualinherited
Returns
true iff this mode provides authentication as well as confidentiality.

Reimplemented from Botan::Cipher_Mode.

Definition at line 47 of file aead.h.

47 { return true; }

◆ block_size()

size_t Botan::OCB_Mode::block_size ( ) const
inlineprotected

◆ clear()

void Botan::OCB_Mode::clear ( )
overridevirtual

Reset the state.

Implements Botan::SymmetricAlgorithm.

Definition at line 187 of file ocb.cpp.

References m_cipher, m_L, and reset().

188  {
189  m_cipher->clear();
190  m_L.reset(); // add clear here?
191  reset();
192  }
std::unique_ptr< BlockCipher > m_cipher
Definition: ocb.h:63
void reset() override
Definition: ocb.cpp:194
std::unique_ptr< L_computer > m_L
Definition: ocb.h:64

◆ create()

std::unique_ptr< AEAD_Mode > Botan::AEAD_Mode::create ( const std::string &  algo,
Cipher_Dir  direction,
const std::string &  provider = "" 
)
staticinherited

Create an AEAD mode

Parameters
algothe algorithm to create
directionspecify if this should be an encryption or decryption AEAD
provideroptional specification for provider to use
Returns
an AEAD mode or a null pointer if not available

Definition at line 52 of file aead.cpp.

References Botan::SCAN_Name::algo_name(), Botan::SCAN_Name::arg(), Botan::SCAN_Name::arg_as_integer(), Botan::SCAN_Name::arg_count(), Botan::BlockCipher::create(), Botan::ENCRYPTION, Botan::parse_algorithm_name(), Botan::Cipher_Mode::provider(), and Botan::split_on().

Referenced by Botan::Cipher_Mode::create(), Botan::AEAD_Mode::create_or_throw(), and Botan::get_aead().

55  {
56 #if defined(BOTAN_HAS_AEAD_CHACHA20_POLY1305)
57  if(algo == "ChaCha20Poly1305")
58  {
59  if(dir == ENCRYPTION)
60  return std::unique_ptr<AEAD_Mode>(new ChaCha20Poly1305_Encryption);
61  else
62  return std::unique_ptr<AEAD_Mode>(new ChaCha20Poly1305_Decryption);
63 
64  }
65 #endif
66 
67  if(algo.find('/') != std::string::npos)
68  {
69  const std::vector<std::string> algo_parts = split_on(algo, '/');
70  const std::string cipher_name = algo_parts[0];
71  const std::vector<std::string> mode_info = parse_algorithm_name(algo_parts[1]);
72 
73  if(mode_info.empty())
74  return std::unique_ptr<AEAD_Mode>();
75 
76  std::ostringstream alg_args;
77 
78  alg_args << '(' << cipher_name;
79  for(size_t i = 1; i < mode_info.size(); ++i)
80  alg_args << ',' << mode_info[i];
81  for(size_t i = 2; i < algo_parts.size(); ++i)
82  alg_args << ',' << algo_parts[i];
83  alg_args << ')';
84 
85  const std::string mode_name = mode_info[0] + alg_args.str();
86  return AEAD_Mode::create(mode_name, dir);
87  }
88 
89 #if defined(BOTAN_HAS_BLOCK_CIPHER)
90 
91  SCAN_Name req(algo);
92 
93  if(req.arg_count() == 0)
94  {
95  return std::unique_ptr<AEAD_Mode>();
96  }
97 
98  std::unique_ptr<BlockCipher> bc(BlockCipher::create(req.arg(0), provider));
99 
100  if(!bc)
101  {
102  return std::unique_ptr<AEAD_Mode>();
103  }
104 
105 #if defined(BOTAN_HAS_AEAD_CCM)
106  if(req.algo_name() == "CCM")
107  {
108  size_t tag_len = req.arg_as_integer(1, 16);
109  size_t L_len = req.arg_as_integer(2, 3);
110  if(dir == ENCRYPTION)
111  return std::unique_ptr<AEAD_Mode>(new CCM_Encryption(bc.release(), tag_len, L_len));
112  else
113  return std::unique_ptr<AEAD_Mode>(new CCM_Decryption(bc.release(), tag_len, L_len));
114  }
115 #endif
116 
117 #if defined(BOTAN_HAS_AEAD_GCM)
118  if(req.algo_name() == "GCM")
119  {
120  size_t tag_len = req.arg_as_integer(1, 16);
121  if(dir == ENCRYPTION)
122  return std::unique_ptr<AEAD_Mode>(new GCM_Encryption(bc.release(), tag_len));
123  else
124  return std::unique_ptr<AEAD_Mode>(new GCM_Decryption(bc.release(), tag_len));
125  }
126 #endif
127 
128 #if defined(BOTAN_HAS_AEAD_OCB)
129  if(req.algo_name() == "OCB")
130  {
131  size_t tag_len = req.arg_as_integer(1, 16);
132  if(dir == ENCRYPTION)
133  return std::unique_ptr<AEAD_Mode>(new OCB_Encryption(bc.release(), tag_len));
134  else
135  return std::unique_ptr<AEAD_Mode>(new OCB_Decryption(bc.release(), tag_len));
136  }
137 #endif
138 
139 #if defined(BOTAN_HAS_AEAD_EAX)
140  if(req.algo_name() == "EAX")
141  {
142  size_t tag_len = req.arg_as_integer(1, bc->block_size());
143  if(dir == ENCRYPTION)
144  return std::unique_ptr<AEAD_Mode>(new EAX_Encryption(bc.release(), tag_len));
145  else
146  return std::unique_ptr<AEAD_Mode>(new EAX_Decryption(bc.release(), tag_len));
147  }
148 #endif
149 
150 #if defined(BOTAN_HAS_AEAD_SIV)
151  if(req.algo_name() == "SIV")
152  {
153  if(dir == ENCRYPTION)
154  return std::unique_ptr<AEAD_Mode>(new SIV_Encryption(bc.release()));
155  else
156  return std::unique_ptr<AEAD_Mode>(new SIV_Decryption(bc.release()));
157  }
158 #endif
159 
160 #endif
161 
162  return std::unique_ptr<AEAD_Mode>();
163  }
std::vector< std::string > split_on(const std::string &str, char delim)
Definition: parsing.cpp:144
static std::unique_ptr< AEAD_Mode > create(const std::string &algo, Cipher_Dir direction, const std::string &provider="")
Definition: aead.cpp:52
std::vector< std::string > parse_algorithm_name(const std::string &namex)
Definition: parsing.cpp:91
static std::unique_ptr< BlockCipher > create(const std::string &algo_spec, const std::string &provider="")
virtual std::string provider() const
Definition: cipher_mode.h:180

◆ create_or_throw()

std::unique_ptr< AEAD_Mode > Botan::AEAD_Mode::create_or_throw ( const std::string &  algo,
Cipher_Dir  direction,
const std::string &  provider = "" 
)
staticinherited

Create an AEAD mode, or throw

Parameters
algothe algorithm to create
directionspecify if this should be an encryption or decryption AEAD
provideroptional specification for provider to use
Returns
an AEAD mode, or throw an exception

Definition at line 42 of file aead.cpp.

References Botan::AEAD_Mode::create().

Referenced by Botan::TLS::Connection_Cipher_State::Connection_Cipher_State(), Botan::TLS::Session::decrypt(), Botan::TLS::Session::encrypt(), Botan::mceies_decrypt(), and Botan::mceies_encrypt().

45  {
46  if(auto aead = AEAD_Mode::create(algo, dir, provider))
47  return aead;
48 
49  throw Lookup_Error("AEAD", algo, provider);
50  }
static std::unique_ptr< AEAD_Mode > create(const std::string &algo, Cipher_Dir direction, const std::string &provider="")
Definition: aead.cpp:52
virtual std::string provider() const
Definition: cipher_mode.h:180

◆ default_nonce_length()

size_t Botan::AEAD_Mode::default_nonce_length ( ) const
inlineoverridevirtualinherited
Returns
default AEAD nonce size (a commonly supported value among AEAD modes, and large enough that random collisions are unlikely)

Implements Botan::Cipher_Mode.

Reimplemented in Botan::TLS::TLS_CBC_HMAC_AEAD_Mode, and Botan::CCM_Mode.

Definition at line 104 of file aead.h.

104 { return 12; }

◆ finish()

virtual void Botan::Cipher_Mode::finish ( secure_vector< uint8_t > &  final_block,
size_t  offset = 0 
)
pure virtualinherited

◆ key_spec()

Key_Length_Specification Botan::OCB_Mode::key_spec ( ) const
overridevirtual
Returns
object describing limits on key size

Implements Botan::SymmetricAlgorithm.

Definition at line 223 of file ocb.cpp.

References m_cipher, and m_L.

224  {
225  return m_cipher->key_spec();
226  }
std::unique_ptr< BlockCipher > m_cipher
Definition: ocb.h:63

◆ maximum_keylength()

size_t Botan::SymmetricAlgorithm::maximum_keylength ( ) const
inlineinherited
Returns
minimum allowed key length

Definition at line 38 of file sym_algo.h.

39  {
40  return key_spec().maximum_keylength();
41  }
size_t maximum_keylength() const
Definition: key_spec.h:69
virtual Key_Length_Specification key_spec() const =0

◆ minimum_final_size()

virtual size_t Botan::Cipher_Mode::minimum_final_size ( ) const
pure virtualinherited

◆ minimum_keylength()

size_t Botan::SymmetricAlgorithm::minimum_keylength ( ) const
inlineinherited
Returns
maximum allowed key length

Definition at line 46 of file sym_algo.h.

Referenced by botan_block_cipher_get_keyspec(), and botan_mac_get_keyspec().

47  {
48  return key_spec().minimum_keylength();
49  }
virtual Key_Length_Specification key_spec() const =0
size_t minimum_keylength() const
Definition: key_spec.h:61

◆ name()

std::string Botan::OCB_Mode::name ( ) const
overridevirtual
Returns
the algorithm name

Implements Botan::SymmetricAlgorithm.

Definition at line 213 of file ocb.cpp.

References m_cipher.

Referenced by set_associated_data().

214  {
215  return m_cipher->name() + "/OCB"; // include tag size?
216  }
std::unique_ptr< BlockCipher > m_cipher
Definition: ocb.h:63

◆ output_length()

virtual size_t Botan::Cipher_Mode::output_length ( size_t  input_length) const
pure virtualinherited

◆ par_blocks()

size_t Botan::OCB_Mode::par_blocks ( ) const
inlineprotected

Definition at line 59 of file ocb.h.

Referenced by Botan::OCB_Encryption::finish(), and set_associated_data().

59 { return m_par_blocks; }

◆ par_bytes()

size_t Botan::OCB_Mode::par_bytes ( ) const
inlineprotected

Definition at line 60 of file ocb.h.

60 { return m_checksum.size(); }
secure_vector< uint8_t > m_checksum
Definition: ocb.h:68

◆ process()

virtual size_t Botan::Cipher_Mode::process ( uint8_t  msg[],
size_t  msg_len 
)
pure virtualinherited

Process message blocks

Input must be a multiple of update_granularity

Processes msg in place and returns bytes written. Normally this will be either msg_len (indicating the entire message was processed) or for certain AEAD modes zero (indicating that the mode requires the entire message be processed in one pass).

Parameters
msgthe message to be processed
msg_lenlength of the message in bytes

Implemented in Botan::OCB_Decryption, Botan::CBC_Decryption, Botan::EAX_Decryption, Botan::GCM_Decryption, Botan::OCB_Encryption, Botan::CFB_Decryption, Botan::ChaCha20Poly1305_Decryption, Botan::XTS_Decryption, Botan::EAX_Encryption, Botan::GCM_Encryption, Botan::CBC_Encryption, Botan::CFB_Encryption, Botan::ChaCha20Poly1305_Encryption, Botan::XTS_Encryption, Botan::TLS::TLS_CBC_HMAC_AEAD_Mode, Botan::SIV_Mode, and Botan::CCM_Mode.

Referenced by Botan::TLS::check_tls_cbc_padding(), and Botan::TLS::TLS_CBC_HMAC_AEAD_Encryption::set_associated_data().

◆ provider()

virtual std::string Botan::Cipher_Mode::provider ( ) const
inlinevirtualinherited
Returns
provider information about this implementation. Default is "base", might also return "sse2", "avx2", "openssl", or some other arbitrary string.

Reimplemented in Botan::GCM_Mode.

Definition at line 180 of file cipher_mode.h.

Referenced by Botan::AEAD_Mode::create(), and Botan::Cipher_Mode::create().

180 { return "base"; }

◆ providers()

std::vector< std::string > Botan::Cipher_Mode::providers ( const std::string &  algo_spec)
staticinherited
Returns
list of available providers for this algorithm, empty if not available
Parameters
algo_specalgorithm name

Definition at line 190 of file cipher_mode.cpp.

References Botan::Cipher_Mode::create(), and Botan::ENCRYPTION.

191  {
192  const std::vector<std::string>& possible = { "base", "openssl", "commoncrypto" };
193  std::vector<std::string> providers;
194  for(auto&& prov : possible)
195  {
196  std::unique_ptr<Cipher_Mode> mode = Cipher_Mode::create(algo_spec, ENCRYPTION, prov);
197  if(mode)
198  {
199  providers.push_back(prov); // available
200  }
201  }
202  return providers;
203  }
static std::unique_ptr< Cipher_Mode > create(const std::string &algo, Cipher_Dir direction, const std::string &provider="")
Definition: cipher_mode.cpp:54
static std::vector< std::string > providers(const std::string &algo_spec)

◆ reset()

void Botan::OCB_Mode::reset ( )
overridevirtual

Resets just the message specific state and allows encrypting again under the existing key

Implements Botan::Cipher_Mode.

Definition at line 194 of file ocb.cpp.

References m_ad_hash, m_block_index, m_checksum, and Botan::zeroise().

Referenced by clear().

195  {
196  m_block_index = 0;
199  m_last_nonce.clear();
200  m_stretch.clear();
201  }
secure_vector< uint8_t > m_ad_hash
Definition: ocb.h:69
secure_vector< uint8_t > m_checksum
Definition: ocb.h:68
size_t m_block_index
Definition: ocb.h:66
void zeroise(std::vector< T, Alloc > &vec)
Definition: secmem.h:160

◆ set_ad()

template<typename Alloc >
void Botan::AEAD_Mode::set_ad ( const std::vector< uint8_t, Alloc > &  ad)
inlineinherited

Set associated data that is not included in the ciphertext but that should be authenticated. Must be called after set_key and before start.

See set_associated_data().

Parameters
adthe associated data

Definition at line 95 of file aead.h.

Referenced by Botan::TLS::write_record().

96  {
97  set_associated_data(ad.data(), ad.size());
98  }
virtual void set_associated_data(const uint8_t ad[], size_t ad_len)=0

◆ set_associated_data()

void Botan::OCB_Mode::set_associated_data ( const uint8_t  ad[],
size_t  ad_len 
)
overridevirtual

Set associated data that is not included in the ciphertext but that should be authenticated. Must be called after set_key and before start.

Unless reset by another call, the associated data is kept between messages. Thus, if the AD does not change, calling once (after set_key) is the optimum.

Parameters
adthe associated data
ad_lenlength of add in bytes

Implements Botan::AEAD_Mode.

Definition at line 234 of file ocb.cpp.

References block_size(), BOTAN_ASSERT, BOTAN_STATE_CHECK, Botan::copy_mem(), m_ad_hash, m_block_index, m_checksum, m_cipher, m_L, name(), par_blocks(), tag_size(), valid_nonce_length(), Botan::SymmetricAlgorithm::verify_key_set(), Botan::xor_buf(), and Botan::zeroise().

235  {
236  verify_key_set(m_L != nullptr);
237  m_ad_hash = ocb_hash(*m_L, *m_cipher, ad, ad_len);
238  }
std::unique_ptr< BlockCipher > m_cipher
Definition: ocb.h:63
void verify_key_set(bool cond) const
Definition: sym_algo.h:89
std::unique_ptr< L_computer > m_L
Definition: ocb.h:64
secure_vector< uint8_t > m_ad_hash
Definition: ocb.h:69

◆ set_associated_data_vec()

template<typename Alloc >
void Botan::AEAD_Mode::set_associated_data_vec ( const std::vector< uint8_t, Alloc > &  ad)
inlineinherited

Set associated data that is not included in the ciphertext but that should be authenticated. Must be called after set_key and before start.

See set_associated_data().

Parameters
adthe associated data

Definition at line 80 of file aead.h.

Referenced by Botan::TLS::write_record().

81  {
82  set_associated_data(ad.data(), ad.size());
83  }
virtual void set_associated_data(const uint8_t ad[], size_t ad_len)=0

◆ set_key() [1/3]

void Botan::SymmetricAlgorithm::set_key ( const SymmetricKey key)
inlineinherited

◆ set_key() [2/3]

template<typename Alloc >
void Botan::SymmetricAlgorithm::set_key ( const std::vector< uint8_t, Alloc > &  key)
inlineinherited

Definition at line 71 of file sym_algo.h.

References name.

72  {
73  set_key(key.data(), key.size());
74  }
void set_key(const SymmetricKey &key)
Definition: sym_algo.h:65

◆ set_key() [3/3]

void Botan::SymmetricAlgorithm::set_key ( const uint8_t  key[],
size_t  length 
)
inherited

Set the symmetric key of this object.

Parameters
keythe to be set as a byte array.
lengthin bytes of key param

Definition at line 17 of file sym_algo.cpp.

References Botan::SymmetricAlgorithm::name(), and Botan::SymmetricAlgorithm::valid_keylength().

18  {
19  if(!valid_keylength(length))
20  throw Invalid_Key_Length(name(), length);
21  key_schedule(key, length);
22  }
bool valid_keylength(size_t length) const
Definition: sym_algo.h:56
virtual std::string name() const =0

◆ start() [1/3]

template<typename Alloc >
void Botan::Cipher_Mode::start ( const std::vector< uint8_t, Alloc > &  nonce)
inlineinherited

Begin processing a message.

Parameters
noncethe per message nonce

Definition at line 69 of file cipher_mode.h.

Referenced by botan_cipher_start(), Botan::TLS::check_tls_cbc_padding(), Botan::TLS::TLS_CBC_HMAC_AEAD_Encryption::set_associated_data(), and Botan::TLS::write_record().

70  {
71  start_msg(nonce.data(), nonce.size());
72  }
virtual void start_msg(const uint8_t nonce[], size_t nonce_len)=0

◆ start() [2/3]

void Botan::Cipher_Mode::start ( const uint8_t  nonce[],
size_t  nonce_len 
)
inlineinherited

Begin processing a message.

Parameters
noncethe per message nonce
nonce_lenlength of nonce

Definition at line 79 of file cipher_mode.h.

80  {
81  start_msg(nonce, nonce_len);
82  }
virtual void start_msg(const uint8_t nonce[], size_t nonce_len)=0

◆ start() [3/3]

void Botan::Cipher_Mode::start ( )
inlineinherited

Begin processing a message.

Definition at line 87 of file cipher_mode.h.

88  {
89  return start_msg(nullptr, 0);
90  }
virtual void start_msg(const uint8_t nonce[], size_t nonce_len)=0

◆ tag_size()

size_t Botan::OCB_Mode::tag_size ( ) const
inlineoverridevirtual
Returns
the size of the authentication tag used (in bytes)

Reimplemented from Botan::Cipher_Mode.

Definition at line 44 of file ocb.h.

Referenced by Botan::OCB_Encryption::finish(), Botan::OCB_Decryption::finish(), and set_associated_data().

44 { return m_tag_size; }

◆ update()

void Botan::Cipher_Mode::update ( secure_vector< uint8_t > &  buffer,
size_t  offset = 0 
)
inlineinherited

Process some data. Input must be in size update_granularity() uint8_t blocks.

Parameters
bufferin/out parameter which will possibly be resized
offsetan offset into blocks to begin processing

Definition at line 112 of file cipher_mode.h.

References BOTAN_ASSERT.

Referenced by botan_cipher_update(), Botan::XTS_Encryption::finish(), Botan::ChaCha20Poly1305_Encryption::finish(), Botan::CFB_Encryption::finish(), Botan::CBC_Encryption::finish(), Botan::EAX_Encryption::finish(), Botan::XTS_Decryption::finish(), Botan::CFB_Decryption::finish(), Botan::CTS_Encryption::finish(), Botan::CBC_Decryption::finish(), Botan::TLS::TLS_CBC_HMAC_AEAD_Encryption::finish(), Botan::CTS_Decryption::finish(), and Botan::TLS::TLS_CBC_HMAC_AEAD_Decryption::finish().

113  {
114  BOTAN_ASSERT(buffer.size() >= offset, "Offset ok");
115  uint8_t* buf = buffer.data() + offset;
116  const size_t buf_size = buffer.size() - offset;
117 
118  const size_t written = process(buf, buf_size);
119  buffer.resize(offset + written);
120  }
#define BOTAN_ASSERT(expr, assertion_made)
Definition: assert.h:55
virtual size_t process(uint8_t msg[], size_t msg_len)=0

◆ update_granularity()

size_t Botan::OCB_Mode::update_granularity ( ) const
overridevirtual
Returns
size of required blocks to update

Implements Botan::Cipher_Mode.

Definition at line 218 of file ocb.cpp.

References block_size().

Referenced by Botan::OCB_Encryption::process(), and Botan::OCB_Decryption::process().

219  {
220  return (m_par_blocks * block_size());
221  }
size_t block_size() const
Definition: ocb.h:58

◆ valid_keylength()

bool Botan::SymmetricAlgorithm::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 56 of file sym_algo.h.

Referenced by Botan::aont_package(), Botan::aont_unpackage(), and Botan::SymmetricAlgorithm::set_key().

57  {
58  return key_spec().valid_keylength(length);
59  }
bool valid_keylength(size_t length) const
Definition: key_spec.h:51
virtual Key_Length_Specification key_spec() const =0

◆ valid_nonce_length()

bool Botan::OCB_Mode::valid_nonce_length ( size_t  nonce_len) const
overridevirtual
Returns
true iff nonce_len is a valid length for the nonce

Implements Botan::Cipher_Mode.

Definition at line 203 of file ocb.cpp.

References block_size().

Referenced by set_associated_data().

204  {
205  if(length == 0)
206  return false;
207  if(block_size() == 16)
208  return length < 16;
209  else
210  return length < (block_size() - 1);
211  }
size_t block_size() const
Definition: ocb.h:58

◆ verify_key_set()

void Botan::SymmetricAlgorithm::verify_key_set ( bool  cond) const
inlineprotectedinherited

Definition at line 89 of file sym_algo.h.

Referenced by Botan::Salsa20::cipher(), Botan::CTR_BE::cipher(), Botan::RC4::cipher(), Botan::SHAKE_128_Cipher::cipher(), Botan::ChaCha::cipher(), Botan::Poly1305::clear(), Botan::SHACAL2::decrypt_n(), Botan::MISTY1::decrypt_n(), Botan::IDEA::decrypt_n(), Botan::SM4::decrypt_n(), Botan::CAST_256::decrypt_n(), Botan::SEED::decrypt_n(), Botan::KASUMI::decrypt_n(), Botan::CAST_128::decrypt_n(), Botan::Twofish::decrypt_n(), Botan::DES::decrypt_n(), Botan::Noekeon::decrypt_n(), Botan::XTEA::decrypt_n(), Botan::Blowfish::decrypt_n(), Botan::DESX::decrypt_n(), Botan::Threefish_512::decrypt_n(), Botan::Serpent::decrypt_n(), Botan::Lion::decrypt_n(), Botan::TripleDES::decrypt_n(), Botan::GOST_28147_89::decrypt_n(), Botan::Blowfish::encrypt_n(), Botan::KASUMI::encrypt_n(), Botan::Twofish::encrypt_n(), Botan::XTEA::encrypt_n(), Botan::SM4::encrypt_n(), Botan::CAST_256::encrypt_n(), Botan::MISTY1::encrypt_n(), Botan::DESX::encrypt_n(), Botan::Noekeon::encrypt_n(), Botan::CAST_128::encrypt_n(), Botan::SEED::encrypt_n(), Botan::DES::encrypt_n(), Botan::SHACAL2::encrypt_n(), Botan::IDEA::encrypt_n(), Botan::Threefish_512::encrypt_n(), Botan::Serpent::encrypt_n(), Botan::Lion::encrypt_n(), Botan::TripleDES::encrypt_n(), Botan::GOST_28147_89::encrypt_n(), Botan::OCB_Encryption::finish(), Botan::OCB_Decryption::finish(), Botan::GHASH::ghash_update(), Botan::CFB_Encryption::process(), Botan::CFB_Decryption::process(), Botan::Salsa20::seek(), Botan::CTR_BE::seek(), Botan::ChaCha::seek(), set_associated_data(), Botan::Salsa20::set_iv(), Botan::ChaCha::set_iv(), Botan::GHASH::update(), Botan::GHASH::update_associated_data(), Botan::CFB_Mode::valid_nonce_length(), and Botan::ChaCha::write_keystream().

90  {
91  if(cond == false)
92  throw_key_not_set_error();
93  }

Member Data Documentation

◆ m_ad_hash

secure_vector<uint8_t> Botan::OCB_Mode::m_ad_hash
protected

◆ m_block_index

size_t Botan::OCB_Mode::m_block_index = 0
protected

◆ m_checksum

secure_vector<uint8_t> Botan::OCB_Mode::m_checksum
protected

◆ m_cipher

std::unique_ptr<BlockCipher> Botan::OCB_Mode::m_cipher
protected

◆ m_L

std::unique_ptr<L_computer> Botan::OCB_Mode::m_L
protected

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