Botan 3.13.0
Crypto and TLS for C&
Public Member Functions | Static Public Member Functions | List of all members
Botan::HKDF_Expand Class Referencefinal

#include <hkdf.h>

Inheritance diagram for Botan::HKDF_Expand:
Botan::KDF

Public Member Functions

KDF * clone () const
template<concepts::resizable_byte_buffer T = secure_vector<uint8_t>>
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
template<concepts::resizable_byte_buffer T = secure_vector<uint8_t>>
T derive_key (size_t key_len, const uint8_t secret[], size_t secret_len, std::string_view salt="", std::string_view label="") const
template<concepts::resizable_byte_buffer T = secure_vector<uint8_t>>
T derive_key (size_t key_len, std::span< const uint8_t > secret, const uint8_t salt[], size_t salt_len, std::string_view label="") const
template<concepts::resizable_byte_buffer T = secure_vector<uint8_t>>
T derive_key (size_t key_len, std::span< const uint8_t > secret, std::span< const uint8_t > salt, std::span< const uint8_t > label) const
template<concepts::resizable_byte_buffer T = secure_vector<uint8_t>>
T derive_key (size_t key_len, std::span< const uint8_t > secret, std::string_view salt="", std::string_view label="") const
template<size_t key_len>
std::array< uint8_t, key_len > derive_key (std::span< const uint8_t > secret, std::span< const uint8_t > salt={}, std::span< const uint8_t > label={})
template<size_t key_len>
std::array< uint8_t, key_len > derive_key (std::span< const uint8_t > secret, std::span< const uint8_t > salt={}, std::string_view label="")
template<size_t key_len>
std::array< uint8_t, key_len > derive_key (std::span< const uint8_t > secret, std::string_view salt="", std::string_view label="")
void derive_key (std::span< uint8_t > key, std::span< const uint8_t > secret, std::span< const uint8_t > salt, std::span< const uint8_t > label) const
 HKDF_Expand (std::unique_ptr< MessageAuthenticationCode > prf)
void 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
std::string name () const override
std::unique_ptr< KDF > new_object () const override

Static Public Member Functions

static std::unique_ptr< KDF > create (std::string_view algo_spec, std::string_view provider="")
static std::unique_ptr< KDF > create_or_throw (std::string_view algo_spec, std::string_view provider="")
static std::vector< std::string > providers (std::string_view algo_spec)

Detailed Description

HKDF Expansion Step from RFC 5869.

Definition at line 68 of file hkdf.h.

Constructor & Destructor Documentation

◆ HKDF_Expand()

Botan::HKDF_Expand::HKDF_Expand ( std::unique_ptr< MessageAuthenticationCode > prf)
inlineexplicit
Parameters
prfMAC algorithm to use

Definition at line 73 of file hkdf.h.

73: m_prf(std::move(prf)) {}

Member Function Documentation

◆ clone()

KDF * Botan::KDF::clone ( ) const
inlineinherited

Create a new uninitialized object of the same type

Returns
new object representing the same algorithm as *this

Definition at line 246 of file kdf.h.

246{ return this->new_object().release(); }
Botan::KDF::new_object
virtual std::unique_ptr< KDF > new_object() const =0

References new_object().

◆ create()

std::unique_ptr< KDF > Botan::KDF::create ( std::string_view algo_spec,
std::string_view 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 73 of file kdf.cpp.

73 {
74 const SCAN_Name req(algo_spec);
75
76#if defined(BOTAN_HAS_HKDF)
77 if(req.algo_name() == "HKDF" && req.arg_count() == 1) {
78 if(provider.empty() || provider == "base") {
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 if(provider.empty() || provider == "base") {
85 return kdf_create_mac_or_hash<HKDF_Extract>(req.arg(0));
86 }
87 }
88
89 if(req.algo_name() == "HKDF-Expand" && req.arg_count() == 1) {
90 if(provider.empty() || provider == "base") {
91 return kdf_create_mac_or_hash<HKDF_Expand>(req.arg(0));
92 }
93 }
94#endif
95
96#if defined(BOTAN_HAS_KDF2)
97 if(req.algo_name() == "KDF2" && req.arg_count() == 1) {
98 if(provider.empty() || provider == "base") {
99 if(auto hash = HashFunction::create(req.arg(0))) {
100 return std::make_unique<KDF2>(std::move(hash));
101 }
102 }
103 }
104#endif
105
106#if defined(BOTAN_HAS_KDF1_18033)
107 if(req.algo_name() == "KDF1-18033" && req.arg_count() == 1) {
108 if(provider.empty() || provider == "base") {
109 if(auto hash = HashFunction::create(req.arg(0))) {
110 return std::make_unique<KDF1_18033>(std::move(hash));
111 }
112 }
113 }
114#endif
115
116#if defined(BOTAN_HAS_KDF1)
117 if(req.algo_name() == "KDF1" && req.arg_count() == 1) {
118 if(provider.empty() || provider == "base") {
119 if(auto hash = HashFunction::create(req.arg(0))) {
120 return std::make_unique<KDF1>(std::move(hash));
121 }
122 }
123 }
124#endif
125
126#if defined(BOTAN_HAS_TLS_V12_PRF)
127 if(req.algo_name() == "TLS-12-PRF" && req.arg_count() == 1) {
128 if(provider.empty() || provider == "base") {
129 return kdf_create_mac_or_hash<TLS_12_PRF>(req.arg(0));
130 }
131 }
132#endif
133
134#if defined(BOTAN_HAS_X942_PRF)
135 if(req.algo_name() == "X9.42-PRF" && req.arg_count() == 1) {
136 if(provider.empty() || provider == "base") {
137 return std::make_unique<X942_PRF>(req.arg(0));
138 }
139 }
140#endif
141
142#if defined(BOTAN_HAS_SP800_108)
143 if(req.algo_name() == "SP800-108-Counter" && req.arg_count_between(1, 3)) {
144 if(provider.empty() || provider == "base") {
145 return kdf_create_mac_or_hash<SP800_108_Counter>(
146 req.arg(0), req.arg_as_integer(1, 32), req.arg_as_integer(2, 32));
147 }
148 }
149
150 if(req.algo_name() == "SP800-108-Feedback" && req.arg_count_between(1, 3)) {
151 if(provider.empty() || provider == "base") {
152 return kdf_create_mac_or_hash<SP800_108_Feedback>(
153 req.arg(0), req.arg_as_integer(1, 32), req.arg_as_integer(2, 32));
154 }
155 }
156
157 if(req.algo_name() == "SP800-108-Pipeline" && req.arg_count_between(1, 3)) {
158 if(provider.empty() || provider == "base") {
159 return kdf_create_mac_or_hash<SP800_108_Pipeline>(
160 req.arg(0), req.arg_as_integer(1, 32), req.arg_as_integer(2, 32));
161 }
162 }
163#endif
164
165#if defined(BOTAN_HAS_SP800_56A)
166 if(req.algo_name() == "SP800-56A" && req.arg_count() == 1) {
167 if(provider.empty() || provider == "base") {
168 if(auto hash = HashFunction::create(req.arg(0))) {
169 return std::make_unique<SP800_56C_One_Step_Hash>(std::move(hash));
170 }
171 if(req.arg(0) == "KMAC-128") {
172 return std::make_unique<SP800_56C_One_Step_KMAC128>();
173 }
174 if(req.arg(0) == "KMAC-256") {
175 return std::make_unique<SP800_56C_One_Step_KMAC256>();
176 }
177 if(auto mac = MessageAuthenticationCode::create(req.arg(0))) {
178 return std::make_unique<SP800_56C_One_Step_HMAC>(std::move(mac));
179 }
180 }
181 }
182#endif
183
184#if defined(BOTAN_HAS_SP800_56C)
185 if(req.algo_name() == "SP800-56C" && req.arg_count() == 1) {
186 if(provider.empty() || provider == "base") {
187 std::unique_ptr<KDF> exp(kdf_create_mac_or_hash<SP800_108_Feedback>(req.arg(0), 32, 32));
188 if(exp) {
189 if(auto mac = MessageAuthenticationCode::create(fmt("HMAC({})", req.arg(0)))) {
190 return std::make_unique<SP800_56C_Two_Step>(std::move(mac), std::move(exp));
191 }
192
193 if(auto mac = MessageAuthenticationCode::create(req.arg(0))) {
194 return std::make_unique<SP800_56C_Two_Step>(std::move(mac), std::move(exp));
195 }
196 }
197 }
198 }
199#endif
200
201 BOTAN_UNUSED(req);
202 BOTAN_UNUSED(provider);
203
204 return nullptr;
205}
BOTAN_UNUSED
#define BOTAN_UNUSED
Definition assert.h:144
Botan::HashFunction::create
static std::unique_ptr< HashFunction > create(std::string_view algo_spec, std::string_view provider="")
Definition hash.cpp:111
Botan::MessageAuthenticationCode::create
static std::unique_ptr< MessageAuthenticationCode > create(std::string_view algo_spec, std::string_view provider="")
Definition mac.cpp:50
Botan::fmt
std::string fmt(std::string_view format, const T &... args)
Definition fmt.h:53

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

Referenced by create_or_throw(), and ~KDF().

◆ create_or_throw()

std::unique_ptr< KDF > Botan::KDF::create_or_throw ( std::string_view algo_spec,
std::string_view 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 208 of file kdf.cpp.

208 {
209 if(auto kdf = KDF::create(algo, provider)) {
210 return kdf;
211 }
212 throw Lookup_Error("KDF", algo, provider);
213}
Botan::KDF::create
static std::unique_ptr< KDF > create(std::string_view algo_spec, std::string_view provider="")
Definition kdf.cpp:73
Botan::KDF::kdf
void 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
Definition kdf.h:69

References create(), and kdf().

Referenced by botan_kdf(), Botan::TLS::PSKImporter::derive_imported_psk(), Botan::ECIES_KA_Operation::derive_secret(), Botan::get_kdf(), Botan::PK_Ops::KEM_Decryption_with_KDF::KEM_Decryption_with_KDF(), Botan::PK_Ops::KEM_Encryption_with_KDF::KEM_Encryption_with_KDF(), Botan::PK_Ops::Key_Agreement_with_KDF::Key_Agreement_with_KDF(), Botan::TLS::Callbacks::tls12_protocol_specific_kdf(), and ~KDF().

◆ derive_key() [1/9]

template<concepts::resizable_byte_buffer T = secure_vector<uint8_t>>
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 93 of file kdf.h.

99 {
100 return derive_key<T>(key_len, {secret, secret_len}, {salt, salt_len}, {label, label_len});
101 }
Botan::KDF::derive_key
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:93

References derive_key().

Referenced by derive_key(), derive_key(), derive_key(), derive_key(), derive_key(), Botan::hkdf_expand_label(), and kdf().

◆ derive_key() [2/9]

template<concepts::resizable_byte_buffer T = secure_vector<uint8_t>>
T Botan::KDF::derive_key ( size_t key_len,
const uint8_t secret[],
size_t secret_len,
std::string_view salt = "",
std::string_view 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 181 of file kdf.h.

185 {
186 return derive_key<T>(key_len, {secret, secret_len}, _as_span(salt), _as_span(label));
187 }

References derive_key().

◆ derive_key() [3/9]

template<concepts::resizable_byte_buffer T = secure_vector<uint8_t>>
T Botan::KDF::derive_key ( size_t key_len,
std::span< const uint8_t > secret,
const uint8_t salt[],
size_t salt_len,
std::string_view 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 162 of file kdf.h.

166 {
167 return derive_key<T>(key_len, secret, {salt, salt_len}, _as_span(label));
168 }

References derive_key().

◆ derive_key() [4/9]

template<concepts::resizable_byte_buffer T = secure_vector<uint8_t>>
T Botan::KDF::derive_key ( size_t key_len,
std::span< const uint8_t > secret,
std::span< const uint8_t > salt,
std::span< const uint8_t > 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 142 of file kdf.h.

145 {
146 T key(key_len);
147 perform_kdf(key, secret, salt, label);
148 return key;
149 }
Botan::KDF::perform_kdf
virtual void perform_kdf(std::span< uint8_t > key, std::span< const uint8_t > secret, std::span< const uint8_t > salt, std::span< const uint8_t > label) const =0

References perform_kdf().

◆ derive_key() [5/9]

template<concepts::resizable_byte_buffer T = secure_vector<uint8_t>>
T Botan::KDF::derive_key ( size_t key_len,
std::span< const uint8_t > secret,
std::string_view salt = "",
std::string_view 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 112 of file kdf.h.

115 {
116 return derive_key<T>(key_len, secret, _as_span(salt), _as_span(label));
117 }

References derive_key().

◆ derive_key() [6/9]

template<size_t key_len>
std::array< uint8_t, key_len > Botan::KDF::derive_key ( std::span< const uint8_t > secret,
std::span< const uint8_t > salt = {},
std::span< const uint8_t > label = {} )
inlineinherited

Derive a key

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

Definition at line 198 of file kdf.h.

199 {},
200 std::span<const uint8_t> label = {}) {
201 std::array<uint8_t, key_len> key{};
202 perform_kdf(key, secret, salt, label);
203 return key;
204 }

◆ derive_key() [7/9]

template<size_t key_len>
std::array< uint8_t, key_len > Botan::KDF::derive_key ( std::span< const uint8_t > secret,
std::span< const uint8_t > salt = {},
std::string_view label = "" )
inlineinherited

Derive a key

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

Definition at line 215 of file kdf.h.

216 {},
217 std::string_view label = "") {
218 return derive_key<key_len>(secret, salt, _as_span(label));
219 }

◆ derive_key() [8/9]

template<size_t key_len>
std::array< uint8_t, key_len > Botan::KDF::derive_key ( std::span< const uint8_t > secret,
std::string_view salt = "",
std::string_view label = "" )
inlineinherited

Derive a key

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

Definition at line 230 of file kdf.h.

232 {
233 return derive_key<key_len>(secret, _as_span(salt), _as_span(label));
234 }

References derive_key().

◆ derive_key() [9/9]

void Botan::KDF::derive_key ( std::span< uint8_t > key,
std::span< const uint8_t > secret,
std::span< const uint8_t > salt,
std::span< const uint8_t > label ) const
inlineinherited

Derive a key

Parameters
keythe output buffer for the to-be-derived key
secretthe secret input
salta diversifier
labelpurpose for the derived keying material

Definition at line 126 of file kdf.h.

129 {
130 perform_kdf(key, secret, salt, label);
131 }

References perform_kdf().

◆ kdf()

void Botan::KDF::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
inlineinherited

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

Definition at line 69 of file kdf.h.

76 {
77 derive_key({key, key_len}, {secret, secret_len}, {salt, salt_len}, {label, label_len});
78 }

References derive_key(), and kdf().

Referenced by create_or_throw(), and kdf().

◆ name()

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

Return the name of this KDF

Returns
KDF name

Implements Botan::KDF.

Definition at line 80 of file hkdf.cpp.

80 {
81 return fmt("HKDF-Expand({})", m_prf->name());
82}

References Botan::fmt().

◆ new_object()

std::unique_ptr< KDF > Botan::HKDF_Expand::new_object ( ) const
overridevirtual

Create a new uninitialized object of the same type

Returns
new object representing the same algorithm as *this

Implements Botan::KDF.

Definition at line 76 of file hkdf.cpp.

76 {
77 return std::make_unique<HKDF_Expand>(m_prf->new_object());
78}

◆ providers()

std::vector< std::string > Botan::KDF::providers ( std::string_view algo_spec)
staticinherited

List the providers available for a given KDF

Returns
list of available providers for this algorithm, empty if not available

Definition at line 215 of file kdf.cpp.

215 {
216 return probe_providers_of<KDF>(algo_spec);
217}
Botan::probe_providers_of
std::vector< std::string > probe_providers_of(std::string_view algo_spec, const std::vector< std::string > &possible={"base"})
Definition scan_name.h:99

References Botan::probe_providers_of().

Referenced by ~KDF().

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