Botan  2.6.0
Crypto and TLS for C++11
Public Member Functions | Static Public Member Functions | Protected Member Functions | List of all members
Botan::SIV_Mode Class Referenceabstract

#include <siv.h>

Inheritance diagram for Botan::SIV_Mode:
Botan::AEAD_Mode Botan::Cipher_Mode Botan::SIV_Decryption Botan::SIV_Encryption

Public Member Functions

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
 
virtual size_t minimum_final_size () const =0
 
std::string name () const override
 
virtual size_t output_length (size_t input_length) const =0
 
size_t process (uint8_t buf[], size_t size) override
 
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
 
void set_associated_data_n (size_t n, const uint8_t ad[], size_t ad_len)
 
template<typename Alloc >
void set_associated_data_vec (const std::vector< uint8_t, Alloc > &ad)
 
template<typename Alloc >
void set_key (const std::vector< uint8_t, Alloc > &key)
 
void set_key (const SymmetricKey &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
 
 ~SIV_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
 
StreamCipherctr ()
 
secure_vector< uint8_t > & msg_buf ()
 
secure_vector< uint8_t > S2V (const uint8_t text[], size_t text_len)
 
void set_ctr_iv (secure_vector< uint8_t > V)
 
 SIV_Mode (BlockCipher *cipher)
 

Detailed Description

Base class for SIV encryption and decryption (

See also
RFC 5297)

Definition at line 23 of file siv.h.

Constructor & Destructor Documentation

◆ ~SIV_Mode()

Botan::SIV_Mode::~SIV_Mode ( )

Definition at line 28 of file siv.cpp.

29  {
30  // for ~unique_ptr
31  }

◆ SIV_Mode()

Botan::SIV_Mode::SIV_Mode ( BlockCipher cipher)
explicitprotected

Definition at line 17 of file siv.cpp.

17  :
18  m_name(cipher->name() + "/SIV"),
19  m_ctr(new CTR_BE(cipher->clone(), 8)),
20  m_mac(new CMAC(cipher)),
21  m_bs(cipher->block_size())
22  {
23  // Not really true but only 128 bit allowed at the moment
24  if(m_bs != 16)
25  throw Invalid_Argument("SIV requires a 128 bit block cipher");
26  }

Member Function Documentation

◆ 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::SIV_Mode::block_size ( ) const
inlineprotected

Definition at line 60 of file siv.h.

Referenced by Botan::SIV_Decryption::finish(), S2V(), and set_associated_data_n().

60 { return m_bs; }

◆ clear()

void Botan::SIV_Mode::clear ( )
overridevirtual

Zeroise all state See also reset_msg()

Implements Botan::Cipher_Mode.

Definition at line 33 of file siv.cpp.

References reset().

34  {
35  m_ctr->clear();
36  m_mac->clear();
37  reset();
38  }
void reset() override
Definition: siv.cpp:40

◆ 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:236

◆ 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(), and Botan::Cipher_Mode::provider().

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:236

◆ ctr()

StreamCipher& Botan::SIV_Mode::ctr ( )
inlineprotected

Definition at line 62 of file siv.h.

Referenced by Botan::SIV_Encryption::finish(), Botan::SIV_Decryption::finish(), and set_ctr_iv().

62 { return *m_ctr; }

◆ 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 97 of file aead.h.

97 { 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::SIV_Mode::key_spec ( ) const
overridevirtual
Returns
object describing limits on key size

Implements Botan::Cipher_Mode.

Definition at line 68 of file siv.cpp.

69  {
70  return m_mac->key_spec().multiple(2);
71  }

◆ minimum_final_size()

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

◆ msg_buf()

secure_vector<uint8_t>& Botan::SIV_Mode::msg_buf ( )
inlineprotected

Definition at line 66 of file siv.h.

Referenced by Botan::SIV_Encryption::finish(), and Botan::SIV_Decryption::finish().

66 { return m_msg_buf; }

◆ name()

std::string Botan::SIV_Mode::name ( ) const
overridevirtual

Implements Botan::Cipher_Mode.

Definition at line 47 of file siv.cpp.

Referenced by set_associated_data_n().

48  {
49  return m_name;
50  }

◆ output_length()

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

◆ process()

size_t Botan::SIV_Mode::process ( uint8_t  msg[],
size_t  msg_len 
)
overridevirtual

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

Implements Botan::Cipher_Mode.

Definition at line 106 of file siv.cpp.

107  {
108  // all output is saved for processing in finish
109  m_msg_buf.insert(m_msg_buf.end(), buf, buf + sz);
110  return 0;
111  }

◆ 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 236 of file cipher_mode.h.

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

236 { 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 173 of file cipher_mode.cpp.

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

174  {
175  const std::vector<std::string>& possible = { "base", "openssl" };
176  std::vector<std::string> providers;
177  for(auto&& prov : possible)
178  {
179  std::unique_ptr<Cipher_Mode> mode = Cipher_Mode::create(algo_spec, ENCRYPTION, prov);
180  if(mode)
181  {
182  providers.push_back(prov); // available
183  }
184  }
185  return providers;
186  }
static std::unique_ptr< Cipher_Mode > create(const std::string &algo, Cipher_Dir direction, const std::string &provider="")
Definition: cipher_mode.cpp:50
static std::vector< std::string > providers(const std::string &algo_spec)

◆ reset()

void Botan::SIV_Mode::reset ( )
overridevirtual

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

Implements Botan::Cipher_Mode.

Definition at line 40 of file siv.cpp.

Referenced by clear().

41  {
42  m_nonce.clear();
43  m_msg_buf.clear();
44  m_ad_macs.clear();
45  }

◆ S2V()

secure_vector< uint8_t > Botan::SIV_Mode::S2V ( const uint8_t  text[],
size_t  text_len 
)
protected

Definition at line 113 of file siv.cpp.

References block_size(), Botan::poly_double_n(), and Botan::xor_buf().

Referenced by Botan::SIV_Encryption::finish(), and Botan::SIV_Decryption::finish().

114  {
115  const std::vector<uint8_t> zeros(block_size());
116 
117  secure_vector<uint8_t> V = m_mac->process(zeros.data(), zeros.size());
118 
119  for(size_t i = 0; i != m_ad_macs.size(); ++i)
120  {
121  poly_double_n(V.data(), V.size());
122  V ^= m_ad_macs[i];
123  }
124 
125  if(m_nonce.size())
126  {
127  poly_double_n(V.data(), V.size());
128  V ^= m_nonce;
129  }
130 
131  if(text_len < block_size())
132  {
133  poly_double_n(V.data(), V.size());
134  xor_buf(V.data(), text, text_len);
135  V[text_len] ^= 0x80;
136  return m_mac->process(V);
137  }
138 
139  m_mac->update(text, text_len - block_size());
140  xor_buf(V.data(), &text[text_len - block_size()], block_size());
141  m_mac->update(V);
142 
143  return m_mac->final();
144  }
void xor_buf(uint8_t out[], const uint8_t in[], size_t length)
Definition: mem_ops.h:174
size_t block_size() const
Definition: siv.h:60
void poly_double_n(uint8_t out[], const uint8_t in[], size_t n)
Definition: poly_dbl.cpp:63

◆ 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 88 of file aead.h.

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

89  {
90  set_associated_data(ad.data(), ad.size());
91  }
virtual void set_associated_data(const uint8_t ad[], size_t ad_len)=0

◆ set_associated_data()

void Botan::SIV_Mode::set_associated_data ( const uint8_t  ad[],
size_t  ad_len 
)
inlineoverridevirtual

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 36 of file siv.h.

37  {
38  set_associated_data_n(0, ad, ad_len);
39  }
void set_associated_data_n(size_t n, const uint8_t ad[], size_t ad_len)
Definition: siv.cpp:81

◆ set_associated_data_n()

void Botan::SIV_Mode::set_associated_data_n ( size_t  n,
const uint8_t  ad[],
size_t  ad_len 
)

Sets the nth element of the vector of associated data

Parameters
nindex into the AD vector
adassociated data
ad_lenlength of associated data in bytes

Definition at line 81 of file siv.cpp.

References block_size(), name(), and Botan::ASN1::to_string().

82  {
83  const size_t max_ads = block_size() * 8 - 2;
84  if(n > max_ads)
85  throw Invalid_Argument(name() + " allows no more than " + std::to_string(max_ads) + " ADs");
86 
87  if(n >= m_ad_macs.size())
88  m_ad_macs.resize(n+1);
89 
90  m_ad_macs[n] = m_mac->process(ad, length);
91  }
std::string to_string(const BER_Object &obj)
Definition: asn1_obj.cpp:145
std::string name() const override
Definition: siv.cpp:47
size_t block_size() const
Definition: siv.h:60

◆ 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 73 of file aead.h.

74  {
75  set_associated_data(ad.data(), ad.size());
76  }
virtual void set_associated_data(const uint8_t ad[], size_t ad_len)=0

◆ set_ctr_iv()

void Botan::SIV_Mode::set_ctr_iv ( secure_vector< uint8_t >  V)
protected

Definition at line 146 of file siv.cpp.

References ctr(), and Botan::StreamCipher::set_iv().

Referenced by Botan::SIV_Encryption::finish(), and Botan::SIV_Decryption::finish().

147  {
148  V[m_bs-8] &= 0x7F;
149  V[m_bs-4] &= 0x7F;
150 
151  ctr().set_iv(V.data(), V.size());
152  }
StreamCipher & ctr()
Definition: siv.h:62
virtual void set_iv(const uint8_t iv[], size_t iv_len)=0

◆ set_key() [1/3]

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

Set the symmetric key of this transform

Parameters
keycontains the key material

Definition at line 206 of file cipher_mode.h.

Referenced by botan_cipher_set_key().

207  {
208  set_key(key.data(), key.size());
209  }
void set_key(const std::vector< uint8_t, Alloc > &key)
Definition: cipher_mode.h:206

◆ set_key() [2/3]

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

Set the symmetric key of this transform

Parameters
keycontains the key material

Definition at line 215 of file cipher_mode.h.

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

216  {
217  set_key(key.begin(), key.length());
218  }
void set_key(const std::vector< uint8_t, Alloc > &key)
Definition: cipher_mode.h:206

◆ set_key() [3/3]

void Botan::Cipher_Mode::set_key ( const uint8_t  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 225 of file cipher_mode.h.

226  {
227  if(!valid_keylength(length))
228  throw Invalid_Key_Length(name(), length);
229  key_schedule(key, length);
230  }
virtual std::string name() const =0
bool valid_keylength(size_t length) const
Definition: cipher_mode.h:196

◆ 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 72 of file cipher_mode.h.

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

73  {
74  start_msg(nonce.data(), nonce.size());
75  }
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 82 of file cipher_mode.h.

83  {
84  start_msg(nonce, nonce_len);
85  }
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 90 of file cipher_mode.h.

91  {
92  return start_msg(nullptr, 0);
93  }
virtual void start_msg(const uint8_t nonce[], size_t nonce_len)=0

◆ tag_size()

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

Reimplemented from Botan::Cipher_Mode.

Definition at line 53 of file siv.h.

Referenced by Botan::SIV_Decryption::finish().

53 { return 16; }

◆ 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 115 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().

116  {
117  BOTAN_ASSERT(buffer.size() >= offset, "Offset ok");
118  uint8_t* buf = buffer.data() + offset;
119  const size_t buf_size = buffer.size() - offset;
120 
121  const size_t written = process(buf, buf_size);
122  buffer.resize(offset + written);
123  }
#define BOTAN_ASSERT(expr, assertion_made)
Definition: assert.h:30
virtual size_t process(uint8_t msg[], size_t msg_len)=0

◆ update_granularity()

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

Implements Botan::Cipher_Mode.

Definition at line 57 of file siv.cpp.

58  {
59  /*
60  This value does not particularly matter as regardless SIV_Mode::update
61  buffers all input, so in theory this could be 1. However as for instance
62  Transform_Filter creates update_granularity() uint8_t buffers, use a
63  somewhat large size to avoid bouncing on a tiny buffer.
64  */
65  return 128;
66  }

◆ valid_keylength()

bool Botan::Cipher_Mode::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 196 of file cipher_mode.h.

197  {
198  return key_spec().valid_keylength(length);
199  }
virtual Key_Length_Specification key_spec() const =0
bool valid_keylength(size_t length) const
Definition: key_spec.h:51

◆ valid_nonce_length()

bool Botan::SIV_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 52 of file siv.cpp.

53  {
54  return true;
55  }

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