Botan  2.7.0
Crypto and TLS for C++11
Public Member Functions | Static Public Member Functions | List of all members
Botan::HKDF_Extract Class Referencefinal

#include <hkdf.h>

Inheritance diagram for Botan::HKDF_Extract:
Botan::KDF

Public Member Functions

KDFclone () const override
 
secure_vector< uint8_t > derive_key (size_t key_len, const uint8_t secret[], size_t secret_len, const uint8_t salt[], size_t salt_len, const uint8_t label[]=nullptr, size_t label_len=0) const
 
secure_vector< uint8_t > derive_key (size_t key_len, const secure_vector< uint8_t > &secret, const std::string &salt="", const std::string &label="") const
 
template<typename Alloc , typename Alloc2 , typename Alloc3 >
secure_vector< uint8_t > derive_key (size_t key_len, const std::vector< uint8_t, Alloc > &secret, const std::vector< uint8_t, Alloc2 > &salt, const std::vector< uint8_t, Alloc3 > &label) const
 
secure_vector< uint8_t > derive_key (size_t key_len, const secure_vector< uint8_t > &secret, const uint8_t salt[], size_t salt_len, const std::string &label="") const
 
secure_vector< uint8_t > derive_key (size_t key_len, const uint8_t secret[], size_t secret_len, const std::string &salt="", const std::string &label="") const
 
 HKDF_Extract (MessageAuthenticationCode *prf)
 
size_t kdf (uint8_t key[], size_t key_len, const uint8_t secret[], size_t secret_len, const uint8_t salt[], size_t salt_len, const uint8_t label[], size_t label_len) const override
 
std::string name () const override
 

Static Public Member Functions

static std::unique_ptr< KDFcreate (const std::string &algo_spec, const std::string &provider="")
 
static std::unique_ptr< KDFcreate_or_throw (const std::string &algo_spec, const std::string &provider="")
 
static std::vector< std::string > providers (const std::string &algo_spec)
 

Detailed Description

HKDF Extraction Step from RFC 5869.

Definition at line 44 of file hkdf.h.

Constructor & Destructor Documentation

◆ HKDF_Extract()

Botan::HKDF_Extract::HKDF_Extract ( MessageAuthenticationCode prf)
inlineexplicit
Parameters
prfMAC algorithm to use

Definition at line 50 of file hkdf.h.

50 : m_prf(prf) {}

Member Function Documentation

◆ clone()

KDF* Botan::HKDF_Extract::clone ( ) const
inlineoverridevirtual
Returns
new object representing the same algorithm as *this

Implements Botan::KDF.

Definition at line 52 of file hkdf.h.

52 { return new HKDF_Extract(m_prf->clone()); }
HKDF_Extract(MessageAuthenticationCode *prf)
Definition: hkdf.h:50

◆ create()

std::unique_ptr< KDF > Botan::KDF::create ( const std::string &  algo_spec,
const std::string &  provider = "" 
)
staticinherited

Create an instance based on a name If provider is empty then best available is chosen.

Parameters
algo_specalgorithm name
providerprovider implementation to choose
Returns
a null pointer if the algo/provider combination cannot be found

Definition at line 69 of file kdf.cpp.

References Botan::SCAN_Name::algo_name(), Botan::SCAN_Name::arg(), Botan::SCAN_Name::arg_count(), BOTAN_UNUSED, Botan::HashFunction::create(), Botan::MessageAuthenticationCode::create(), and hash.

Referenced by Botan::KDF::create_or_throw(), and Botan::get_kdf().

71  {
72  const SCAN_Name req(algo_spec);
73 
74 #if defined(BOTAN_HAS_HKDF)
75  if(req.algo_name() == "HKDF" && req.arg_count() == 1)
76  {
77  if(provider.empty() || provider == "base")
78  {
79  return kdf_create_mac_or_hash<HKDF>(req.arg(0));
80  }
81  }
82 
83  if(req.algo_name() == "HKDF-Extract" && req.arg_count() == 1)
84  {
85  if(provider.empty() || provider == "base")
86  {
87  return kdf_create_mac_or_hash<HKDF_Extract>(req.arg(0));
88  }
89  }
90 
91  if(req.algo_name() == "HKDF-Expand" && req.arg_count() == 1)
92  {
93  if(provider.empty() || provider == "base")
94  {
95  return kdf_create_mac_or_hash<HKDF_Expand>(req.arg(0));
96  }
97  }
98 #endif
99 
100 #if defined(BOTAN_HAS_KDF2)
101  if(req.algo_name() == "KDF2" && req.arg_count() == 1)
102  {
103  if(provider.empty() || provider == "base")
104  {
105  if(auto hash = HashFunction::create(req.arg(0)))
106  return std::unique_ptr<KDF>(new KDF2(hash.release()));
107  }
108  }
109 #endif
110 
111 #if defined(BOTAN_HAS_KDF1_18033)
112  if(req.algo_name() == "KDF1-18033" && req.arg_count() == 1)
113  {
114  if(provider.empty() || provider == "base")
115  {
116  if(auto hash = HashFunction::create(req.arg(0)))
117  return std::unique_ptr<KDF>(new KDF1_18033(hash.release()));
118  }
119  }
120 #endif
121 
122 #if defined(BOTAN_HAS_KDF1)
123  if(req.algo_name() == "KDF1" && req.arg_count() == 1)
124  {
125  if(provider.empty() || provider == "base")
126  {
127  if(auto hash = HashFunction::create(req.arg(0)))
128  return std::unique_ptr<KDF>(new KDF1(hash.release()));
129  }
130  }
131 #endif
132 
133 #if defined(BOTAN_HAS_TLS_V10_PRF)
134  if(req.algo_name() == "TLS-PRF" && req.arg_count() == 0)
135  {
136  if(provider.empty() || provider == "base")
137  {
138  return std::unique_ptr<KDF>(new TLS_PRF);
139  }
140  }
141 #endif
142 
143 #if defined(BOTAN_HAS_TLS_V12_PRF)
144  if(req.algo_name() == "TLS-12-PRF" && req.arg_count() == 1)
145  {
146  if(provider.empty() || provider == "base")
147  {
148  return kdf_create_mac_or_hash<TLS_12_PRF>(req.arg(0));
149  }
150  }
151 #endif
152 
153 #if defined(BOTAN_HAS_X942_PRF)
154  if(req.algo_name() == "X9.42-PRF" && req.arg_count() == 1)
155  {
156  if(provider.empty() || provider == "base")
157  {
158  return std::unique_ptr<KDF>(new X942_PRF(req.arg(0)));
159  }
160  }
161 #endif
162 
163 #if defined(BOTAN_HAS_SP800_108)
164  if(req.algo_name() == "SP800-108-Counter" && req.arg_count() == 1)
165  {
166  if(provider.empty() || provider == "base")
167  {
168  return kdf_create_mac_or_hash<SP800_108_Counter>(req.arg(0));
169  }
170  }
171 
172  if(req.algo_name() == "SP800-108-Feedback" && req.arg_count() == 1)
173  {
174  if(provider.empty() || provider == "base")
175  {
176  return kdf_create_mac_or_hash<SP800_108_Feedback>(req.arg(0));
177  }
178  }
179 
180  if(req.algo_name() == "SP800-108-Pipeline" && req.arg_count() == 1)
181  {
182  if(provider.empty() || provider == "base")
183  {
184  return kdf_create_mac_or_hash<SP800_108_Pipeline>(req.arg(0));
185  }
186  }
187 #endif
188 
189 #if defined(BOTAN_HAS_SP800_56A)
190  if(req.algo_name() == "SP800-56A" && req.arg_count() == 1)
191  {
192  if(auto hash = HashFunction::create(req.arg(0)))
193  return std::unique_ptr<KDF>(new SP800_56A_Hash(hash.release()));
194  if(auto mac = MessageAuthenticationCode::create(req.arg(0)))
195  return std::unique_ptr<KDF>(new SP800_56A_HMAC(mac.release()));
196  }
197 #endif
198 
199 #if defined(BOTAN_HAS_SP800_56C)
200  if(req.algo_name() == "SP800-56C" && req.arg_count() == 1)
201  {
202  std::unique_ptr<KDF> exp(kdf_create_mac_or_hash<SP800_108_Feedback>(req.arg(0)));
203  if(exp)
204  {
205  if(auto mac = MessageAuthenticationCode::create(req.arg(0)))
206  return std::unique_ptr<KDF>(new SP800_56C(mac.release(), exp.release()));
207 
208  if(auto mac = MessageAuthenticationCode::create("HMAC(" + req.arg(0) + ")"))
209  return std::unique_ptr<KDF>(new SP800_56C(mac.release(), exp.release()));
210  }
211  }
212 #endif
213 
214  BOTAN_UNUSED(req);
215  BOTAN_UNUSED(provider);
216 
217  return nullptr;
218  }
static std::unique_ptr< MessageAuthenticationCode > create(const std::string &algo_spec, const std::string &provider="")
Definition: mac.cpp:46
static std::unique_ptr< HashFunction > create(const std::string &algo_spec, const std::string &provider="")
Definition: hash.cpp:106
#define BOTAN_UNUSED(...)
Definition: assert.h:130
MechanismType hash

◆ create_or_throw()

std::unique_ptr< KDF > Botan::KDF::create_or_throw ( const std::string &  algo_spec,
const std::string &  provider = "" 
)
staticinherited

Create an instance based on a name, or throw if the algo/provider combination cannot be found. If provider is empty then best available is chosen.

Definition at line 222 of file kdf.cpp.

References Botan::KDF::create(), and Botan::KDF::kdf().

Referenced by Botan::ECIES_KA_Operation::derive_secret().

224  {
225  if(auto kdf = KDF::create(algo, provider))
226  {
227  return kdf;
228  }
229  throw Lookup_Error("KDF", algo, provider);
230  }
static std::unique_ptr< KDF > create(const std::string &algo_spec, const std::string &provider="")
Definition: kdf.cpp:69
virtual size_t kdf(uint8_t key[], size_t key_len, const uint8_t secret[], size_t secret_len, const uint8_t salt[], size_t salt_len, const uint8_t label[], size_t label_len) const =0

◆ derive_key() [1/5]

secure_vector<uint8_t> Botan::KDF::derive_key ( size_t  key_len,
const uint8_t  secret[],
size_t  secret_len,
const uint8_t  salt[],
size_t  salt_len,
const uint8_t  label[] = nullptr,
size_t  label_len = 0 
) const
inlineinherited

Derive a key

Parameters
key_lenthe desired output length in bytes
secretthe secret input
secret_lensize of secret in bytes
salta diversifier
salt_lensize of salt in bytes
labelpurpose for the derived keying material
label_lensize of label in bytes
Returns
the derived key

Definition at line 83 of file kdf.h.

References salt_len.

90  {
91  secure_vector<uint8_t> key(key_len);
92  key.resize(kdf(key.data(), key.size(), secret, secret_len, salt, salt_len, label, label_len));
93  return key;
94  }
size_t salt_len
Definition: x509_obj.cpp:26
virtual size_t kdf(uint8_t key[], size_t key_len, const uint8_t secret[], size_t secret_len, const uint8_t salt[], size_t salt_len, const uint8_t label[], size_t label_len) const =0

◆ derive_key() [2/5]

secure_vector<uint8_t> Botan::KDF::derive_key ( size_t  key_len,
const secure_vector< uint8_t > &  secret,
const std::string &  salt = "",
const std::string &  label = "" 
) const
inlineinherited

Derive a key

Parameters
key_lenthe desired output length in bytes
secretthe secret input
salta diversifier
labelpurpose for the derived keying material
Returns
the derived key

Definition at line 104 of file kdf.h.

References Botan::cast_char_ptr_to_uint8().

108  {
109  return derive_key(key_len, secret.data(), secret.size(),
110  cast_char_ptr_to_uint8(salt.data()),
111  salt.length(),
112  cast_char_ptr_to_uint8(label.data()),
113  label.length());
114 
115  }
const uint8_t * cast_char_ptr_to_uint8(const char *s)
Definition: mem_ops.h:131
secure_vector< uint8_t > derive_key(size_t key_len, const uint8_t secret[], size_t secret_len, const uint8_t salt[], size_t salt_len, const uint8_t label[]=nullptr, size_t label_len=0) const
Definition: kdf.h:83

◆ derive_key() [3/5]

template<typename Alloc , typename Alloc2 , typename Alloc3 >
secure_vector<uint8_t> Botan::KDF::derive_key ( size_t  key_len,
const std::vector< uint8_t, Alloc > &  secret,
const std::vector< uint8_t, Alloc2 > &  salt,
const std::vector< uint8_t, Alloc3 > &  label 
) const
inlineinherited

Derive a key

Parameters
key_lenthe desired output length in bytes
secretthe secret input
salta diversifier
labelpurpose for the derived keying material
Returns
the derived key

Definition at line 126 of file kdf.h.

130  {
131  return derive_key(key_len,
132  secret.data(), secret.size(),
133  salt.data(), salt.size(),
134  label.data(), label.size());
135  }
secure_vector< uint8_t > derive_key(size_t key_len, const uint8_t secret[], size_t secret_len, const uint8_t salt[], size_t salt_len, const uint8_t label[]=nullptr, size_t label_len=0) const
Definition: kdf.h:83

◆ derive_key() [4/5]

secure_vector<uint8_t> Botan::KDF::derive_key ( size_t  key_len,
const secure_vector< uint8_t > &  secret,
const uint8_t  salt[],
size_t  salt_len,
const std::string &  label = "" 
) const
inlineinherited

Derive a key

Parameters
key_lenthe desired output length in bytes
secretthe secret input
salta diversifier
salt_lensize of salt in bytes
labelpurpose for the derived keying material
Returns
the derived key

Definition at line 146 of file kdf.h.

References Botan::cast_char_ptr_to_uint8(), and salt_len.

151  {
152  return derive_key(key_len,
153  secret.data(), secret.size(),
154  salt, salt_len,
155  cast_char_ptr_to_uint8(label.data()),
156  label.size());
157  }
const uint8_t * cast_char_ptr_to_uint8(const char *s)
Definition: mem_ops.h:131
secure_vector< uint8_t > derive_key(size_t key_len, const uint8_t secret[], size_t secret_len, const uint8_t salt[], size_t salt_len, const uint8_t label[]=nullptr, size_t label_len=0) const
Definition: kdf.h:83
size_t salt_len
Definition: x509_obj.cpp:26

◆ derive_key() [5/5]

secure_vector<uint8_t> Botan::KDF::derive_key ( size_t  key_len,
const uint8_t  secret[],
size_t  secret_len,
const std::string &  salt = "",
const std::string &  label = "" 
) const
inlineinherited

Derive a key

Parameters
key_lenthe desired output length in bytes
secretthe secret input
secret_lensize of secret in bytes
salta diversifier
labelpurpose for the derived keying material
Returns
the derived key

Definition at line 168 of file kdf.h.

References Botan::cast_char_ptr_to_uint8().

173  {
174  return derive_key(key_len, secret, secret_len,
175  cast_char_ptr_to_uint8(salt.data()),
176  salt.length(),
177  cast_char_ptr_to_uint8(label.data()),
178  label.length());
179  }
const uint8_t * cast_char_ptr_to_uint8(const char *s)
Definition: mem_ops.h:131
secure_vector< uint8_t > derive_key(size_t key_len, const uint8_t secret[], size_t secret_len, const uint8_t salt[], size_t salt_len, const uint8_t label[]=nullptr, size_t label_len=0) const
Definition: kdf.h:83

◆ kdf()

size_t Botan::HKDF_Extract::kdf ( uint8_t  key[],
size_t  key_len,
const uint8_t  secret[],
size_t  secret_len,
const uint8_t  salt[],
size_t  salt_len,
const uint8_t  label[],
size_t  label_len 
) const
overridevirtual

Derive a key

Parameters
keybuffer holding the derived key, must be of length key_len
key_lenthe desired output length in bytes
secretthe secret input
secret_lensize of secret in bytes
salta diversifier
salt_lensize of salt in bytes
labelpurpose for the derived keying material
label_lensize of label in bytes
Returns
the derived key

Implements Botan::KDF.

Definition at line 26 of file hkdf.cpp.

References Botan::copy_mem(), and salt_len.

30  {
31  secure_vector<uint8_t> prk;
32  if(salt_len == 0)
33  {
34  m_prf->set_key(std::vector<uint8_t>(m_prf->output_length()));
35  }
36  else
37  {
38  m_prf->set_key(salt, salt_len);
39  }
40 
41  m_prf->update(secret, secret_len);
42  m_prf->final(prk);
43 
44  const size_t written = std::min(prk.size(), key_len);
45  copy_mem(&key[0], prk.data(), written);
46  return written;
47  }
size_t salt_len
Definition: x509_obj.cpp:26
void copy_mem(T *out, const T *in, size_t n)
Definition: mem_ops.h:108

◆ name()

std::string Botan::HKDF_Extract::name ( ) const
inlineoverridevirtual
Returns
KDF name

Implements Botan::KDF.

Definition at line 54 of file hkdf.h.

54 { return "HKDF-Extract(" + m_prf->name() + ")"; }

◆ providers()

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

Definition at line 232 of file kdf.cpp.

233  {
234  return probe_providers_of<KDF>(algo_spec, { "base" });
235  }

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