Botan  2.8.0
Crypto and TLS for C++11
Public Member Functions | Static Public Member Functions | Protected Member Functions | Protected Attributes | Static Protected Attributes | List of all members
Botan::GCM_Encryption Class Referencefinal

#include <gcm.h>

Inheritance diagram for Botan::GCM_Encryption:
Botan::GCM_Mode Botan::AEAD_Mode Botan::Cipher_Mode Botan::SymmetricAlgorithm

Public Member Functions

virtual bool associated_data_requires_key () const
 
bool authenticated () const override
 
void clear () override
 
size_t default_nonce_length () const override
 
void finish (secure_vector< uint8_t > &final_block, size_t offset=0) override
 
 GCM_Encryption (BlockCipher *cipher, size_t tag_size=16)
 
Key_Length_Specification key_spec () const override
 
size_t maximum_keylength () const
 
size_t minimum_final_size () const override
 
size_t minimum_keylength () const
 
std::string name () const override
 
size_t output_length (size_t input_length) const override
 
size_t process (uint8_t buf[], size_t size) override
 
std::string provider () const override
 
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 len) const override
 

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

void verify_key_set (bool cond) const
 

Protected Attributes

const std::string m_cipher_name
 
std::unique_ptr< StreamCipherm_ctr
 
std::unique_ptr< GHASHm_ghash
 
const size_t m_tag_size
 

Static Protected Attributes

static const size_t GCM_BS = 16
 

Detailed Description

GCM Encryption

Definition at line 65 of file gcm.h.

Constructor & Destructor Documentation

◆ GCM_Encryption()

Botan::GCM_Encryption::GCM_Encryption ( BlockCipher cipher,
size_t  tag_size = 16 
)
inline
Parameters
cipherthe 128 bit block cipher to use
tag_sizeis how big the auth tag will be

Definition at line 72 of file gcm.h.

72  :
73  GCM_Mode(cipher, tag_size) {}
GCM_Mode(BlockCipher *cipher, size_t tag_size)
Definition: gcm.cpp:19
size_t tag_size() const override
Definition: gcm.h:37

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; }

◆ clear()

void Botan::GCM_Mode::clear ( )
overridevirtualinherited

Reset the state.

Implements Botan::SymmetricAlgorithm.

Definition at line 38 of file gcm.cpp.

References Botan::GCM_Mode::m_ctr, Botan::GCM_Mode::m_ghash, and Botan::GCM_Mode::reset().

39  {
40  m_ctr->clear();
41  m_ghash->clear();
42  reset();
43  }
std::unique_ptr< StreamCipher > m_ctr
Definition: gcm.h:54
void reset() override
Definition: gcm.cpp:45
std::unique_ptr< GHASH > m_ghash
Definition: gcm.h:55

◆ 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(), 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: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()

void Botan::GCM_Encryption::finish ( secure_vector< uint8_t > &  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::Cipher_Mode.

Definition at line 126 of file gcm.cpp.

References BOTAN_ARG_CHECK, Botan::GCM_Mode::m_ctr, Botan::GCM_Mode::m_ghash, and Botan::GCM_Mode::tag_size().

127  {
128  BOTAN_ARG_CHECK(offset <= buffer.size(), "Invalid offset");
129  const size_t sz = buffer.size() - offset;
130  uint8_t* buf = buffer.data() + offset;
131 
132  m_ctr->cipher(buf, buf, sz);
133  m_ghash->update(buf, sz);
134  auto mac = m_ghash->final();
135  buffer += std::make_pair(mac.data(), tag_size());
136  }
std::unique_ptr< StreamCipher > m_ctr
Definition: gcm.h:54
size_t tag_size() const override
Definition: gcm.h:37
#define BOTAN_ARG_CHECK(expr, msg)
Definition: assert.h:37
std::unique_ptr< GHASH > m_ghash
Definition: gcm.h:55

◆ key_spec()

Key_Length_Specification Botan::GCM_Mode::key_spec ( ) const
overridevirtualinherited
Returns
object describing limits on key size

Implements Botan::SymmetricAlgorithm.

Definition at line 71 of file gcm.cpp.

References Botan::GCM_Mode::m_ctr.

72  {
73  return m_ctr->key_spec();
74  }
std::unique_ptr< StreamCipher > m_ctr
Definition: gcm.h:54

◆ 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()

size_t Botan::GCM_Encryption::minimum_final_size ( ) const
inlineoverridevirtual
Returns
required minimium size to finalize() - may be any length larger than this.

Implements Botan::Cipher_Mode.

Definition at line 78 of file gcm.h.

78 { return 0; }

◆ 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::GCM_Mode::name ( ) const
overridevirtualinherited
Returns
the algorithm name

Implements Botan::SymmetricAlgorithm.

Definition at line 50 of file gcm.cpp.

References Botan::GCM_Mode::m_cipher_name, Botan::GCM_Mode::tag_size(), and Botan::ASN1::to_string().

Referenced by Botan::GCM_Mode::GCM_Mode().

51  {
52  return (m_cipher_name + "/GCM(" + std::to_string(tag_size()) + ")");
53  }
std::string to_string(const BER_Object &obj)
Definition: asn1_obj.cpp:210
const std::string m_cipher_name
Definition: gcm.h:52
size_t tag_size() const override
Definition: gcm.h:37

◆ output_length()

size_t Botan::GCM_Encryption::output_length ( size_t  input_length) const
inlineoverridevirtual

Returns the size of the output if this transform is used to process a message with input_length bytes. In most cases the answer is precise. If it is not possible to precise (namely for CBC decryption) instead a lower bound is returned.

Implements Botan::Cipher_Mode.

Definition at line 75 of file gcm.h.

76  { return input_length + tag_size(); }
size_t tag_size() const override
Definition: gcm.h:37

◆ process()

size_t Botan::GCM_Encryption::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 118 of file gcm.cpp.

References BOTAN_ARG_CHECK, Botan::GCM_Mode::m_ctr, Botan::GCM_Mode::m_ghash, and Botan::GCM_Mode::update_granularity().

119  {
120  BOTAN_ARG_CHECK(sz % update_granularity() == 0, "Invalid buffer size");
121  m_ctr->cipher(buf, buf, sz);
122  m_ghash->update(buf, sz);
123  return sz;
124  }
std::unique_ptr< StreamCipher > m_ctr
Definition: gcm.h:54
size_t update_granularity() const override
Definition: gcm.cpp:60
#define BOTAN_ARG_CHECK(expr, msg)
Definition: assert.h:37
std::unique_ptr< GHASH > m_ghash
Definition: gcm.h:55

◆ provider()

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

Reimplemented from Botan::Cipher_Mode.

Definition at line 55 of file gcm.cpp.

References Botan::GCM_Mode::m_ghash.

56  {
57  return m_ghash->provider();
58  }
std::unique_ptr< GHASH > m_ghash
Definition: gcm.h:55

◆ 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::GCM_Mode::reset ( )
overridevirtualinherited

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

Implements Botan::Cipher_Mode.

Definition at line 45 of file gcm.cpp.

References Botan::GCM_Mode::m_ghash.

Referenced by Botan::GCM_Mode::clear().

46  {
47  m_ghash->reset();
48  }
std::unique_ptr< GHASH > m_ghash
Definition: gcm.h:55

◆ 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::GCM_Mode::set_associated_data ( const uint8_t  ad[],
size_t  ad_len 
)
overridevirtualinherited

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 88 of file gcm.cpp.

References Botan::GCM_Mode::m_ghash.

89  {
90  m_ghash->set_associated_data(ad, ad_len);
91  }
std::unique_ptr< GHASH > m_ghash
Definition: gcm.h:55

◆ 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.

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 the symmetric key of this object.

Parameters
keythe SymmetricKey to be set.

Definition at line 65 of file sym_algo.h.

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

Referenced by Botan::aont_package(), Botan::aont_unpackage(), botan_block_cipher_set_key(), botan_cipher_set_key(), botan_mac_set_key(), Botan::FPE::fe1_decrypt(), and Botan::FPE::fe1_encrypt().

66  {
67  set_key(key.begin(), key.length());
68  }
void set_key(const SymmetricKey &key)
Definition: sym_algo.h:65

◆ 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.

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(), 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::GCM_Mode::tag_size ( ) const
inlineoverridevirtualinherited
Returns
the size of the authentication tag used (in bytes)

Reimplemented from Botan::Cipher_Mode.

Definition at line 37 of file gcm.h.

Referenced by finish(), Botan::GCM_Decryption::finish(), and Botan::GCM_Mode::name().

37 { return m_tag_size; }
const size_t m_tag_size
Definition: gcm.h:51

◆ 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::GCM_Mode::update_granularity ( ) const
overridevirtualinherited
Returns
size of required blocks to update

Implements Botan::Cipher_Mode.

Definition at line 60 of file gcm.cpp.

References Botan::GCM_Mode::GCM_BS.

Referenced by process(), and Botan::GCM_Decryption::process().

61  {
62  return GCM_BS;
63  }
static const size_t GCM_BS
Definition: gcm.h:49

◆ 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::GCM_Mode::valid_nonce_length ( size_t  nonce_len) const
overridevirtualinherited
Returns
true iff nonce_len is a valid length for the nonce

Implements Botan::Cipher_Mode.

Definition at line 65 of file gcm.cpp.

66  {
67  // GCM does not support empty nonces
68  return (len > 0);
69  }

◆ 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::Twofish::decrypt_n(), Botan::CAST_256::decrypt_n(), Botan::Camellia_128::decrypt_n(), Botan::KASUMI::decrypt_n(), Botan::IDEA::decrypt_n(), Botan::Blowfish::decrypt_n(), Botan::AES_128::decrypt_n(), Botan::Noekeon::decrypt_n(), Botan::DES::decrypt_n(), Botan::DESX::decrypt_n(), Botan::MISTY1::decrypt_n(), Botan::SHACAL2::decrypt_n(), Botan::SM4::decrypt_n(), Botan::XTEA::decrypt_n(), Botan::CAST_128::decrypt_n(), Botan::SEED::decrypt_n(), Botan::Serpent::decrypt_n(), Botan::Threefish_512::decrypt_n(), Botan::Lion::decrypt_n(), Botan::ARIA_128::decrypt_n(), Botan::Camellia_192::decrypt_n(), Botan::TripleDES::decrypt_n(), Botan::ARIA_192::decrypt_n(), Botan::Camellia_256::decrypt_n(), Botan::GOST_28147_89::decrypt_n(), Botan::AES_192::decrypt_n(), Botan::ARIA_256::decrypt_n(), Botan::AES_256::decrypt_n(), Botan::SHACAL2::encrypt_n(), Botan::SM4::encrypt_n(), Botan::IDEA::encrypt_n(), Botan::KASUMI::encrypt_n(), Botan::AES_128::encrypt_n(), Botan::MISTY1::encrypt_n(), Botan::Noekeon::encrypt_n(), Botan::CAST_128::encrypt_n(), Botan::SEED::encrypt_n(), Botan::CAST_256::encrypt_n(), Botan::DES::encrypt_n(), Botan::Blowfish::encrypt_n(), Botan::Twofish::encrypt_n(), Botan::XTEA::encrypt_n(), Botan::DESX::encrypt_n(), Botan::Camellia_128::encrypt_n(), Botan::Threefish_512::encrypt_n(), Botan::Serpent::encrypt_n(), Botan::Lion::encrypt_n(), Botan::ARIA_128::encrypt_n(), Botan::Camellia_192::encrypt_n(), Botan::TripleDES::encrypt_n(), Botan::ARIA_192::encrypt_n(), Botan::Camellia_256::encrypt_n(), Botan::GOST_28147_89::encrypt_n(), Botan::AES_192::encrypt_n(), Botan::ARIA_256::encrypt_n(), Botan::AES_256::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(), Botan::OCB_Mode::set_associated_data(), Botan::Salsa20::set_iv(), Botan::ChaCha::set_iv(), Botan::GHASH::update(), Botan::GHASH::update_associated_data(), and Botan::ChaCha::write_keystream().

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

Member Data Documentation

◆ GCM_BS

const size_t Botan::GCM_Mode::GCM_BS = 16
staticprotectedinherited

Definition at line 49 of file gcm.h.

Referenced by Botan::GCM_Mode::GCM_Mode(), and Botan::GCM_Mode::update_granularity().

◆ m_cipher_name

const std::string Botan::GCM_Mode::m_cipher_name
protectedinherited

Definition at line 52 of file gcm.h.

Referenced by Botan::GCM_Mode::name().

◆ m_ctr

std::unique_ptr<StreamCipher> Botan::GCM_Mode::m_ctr
protectedinherited

◆ m_ghash

std::unique_ptr<GHASH> Botan::GCM_Mode::m_ghash
protectedinherited

◆ m_tag_size

const size_t Botan::GCM_Mode::m_tag_size
protectedinherited

Definition at line 51 of file gcm.h.

Referenced by Botan::GCM_Mode::GCM_Mode().


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