mirror of
https://github.com/moparisthebest/mailiverse
synced 2024-11-18 23:15:03 -05:00
38 lines
1.3 KiB
Plaintext
38 lines
1.3 KiB
Plaintext
|
|
.. _key_derivation_function:
|
|
|
|
Key Derivation Functions
|
|
========================================
|
|
|
|
Key derivation functions are used to turn some amount of shared secret
|
|
material into uniform random keys suitable for use with symmetric
|
|
algorithms. An example of an input which is useful for a KDF is a
|
|
shared secret created using Diffie-Hellman key agreement.
|
|
|
|
.. cpp:class:: KDF
|
|
|
|
.. cpp:function:: SecureVector<byte> derive_key( \
|
|
size_t key_len, const MemoryRegion<byte>& secret, \
|
|
const std::string& salt = "") const
|
|
|
|
.. cpp:function:: SecureVector<byte> derive_key( \
|
|
size_t key_len, const MemoryRegion<byte>& secret, \
|
|
const MemoryRegion<byte>& salt) const
|
|
|
|
.. cpp:function:: SecureVector<byte> derive_key( \
|
|
size_t key_len, const MemoryRegion<byte>& secret, \
|
|
const byte* salt, size_t salt_len) const
|
|
|
|
.. cpp:function:: SecureVector<byte> derive_key( \
|
|
size_t key_len, const byte* secret, size_t secret_len, \
|
|
const std::string& salt) const
|
|
|
|
All variations on the same theme. Deterministically creates a
|
|
uniform random value from *secret* and *salt*. Typically *salt* is
|
|
a lable or identifier, such as a session id.
|
|
|
|
You can create a :cpp:class:`KDF` using
|
|
|
|
.. cpp:function:: KDF* get_kdf(const std::string& algo_spec)
|
|
|