Botan::Scrypt Class Reference

#include <scrypt.h>

Inheritance diagram for Botan::Scrypt:

Public Member Functions
void	derive_key (uint8_t out[], size_t out_len, const char *password, size_t password_len, const uint8_t salt[], size_t salt_len) const override
size_t	iterations () const override
size_t	memory_param () const override
size_t	N () const
Scrypt &	operator= (const Scrypt &)=default
size_t	p () const
size_t	parallelism () const override
size_t	r () const
	Scrypt (size_t N, size_t r, size_t p)
	Scrypt (const Scrypt &other)=default
std::string	to_string () const override
size_t	total_memory_usage () const override

Detailed Description

Scrypt key derivation function (RFC 7914)

Definition at line 20 of file scrypt.h.

Constructor & Destructor Documentation

Scrypt() [1/2]

Botan::Scrypt::Scrypt	(	size_t	N,
		size_t	r,
		size_t	p
	)

Definition at line 127 of file scrypt.cpp.

                                           :
   m_N(N), m_r(r), m_p(p)
   {
   if(!is_power_of_2(N))
      throw Invalid_Argument("Scrypt N parameter must be a power of 2");

   if(p == 0 || p > 1024)
      throw Invalid_Argument("Invalid or unsupported scrypt p");
   if(r == 0 || r > 256)
      throw Invalid_Argument("Invalid or unsupported scrypt r");
   if(N < 1 || N > 4194304)
      throw Invalid_Argument("Invalid or unsupported scrypt N");
   }

Scrypt() [2/2]

Botan::Scrypt::Scrypt ( const Scrypt &  other )

default

Member Function Documentation

derive_key()

void Botan::Scrypt::derive_key ( uint8_t  out[], size_t  out_len, const char *  password, size_t  password_len, const uint8_t  salt[], size_t  salt_len  ) const

overridevirtual

Derive a new key under the current Scrypt parameter set

Implements Botan::PasswordHash.

Definition at line 153 of file scrypt.cpp.

References N(), p(), r(), salt_len, and Botan::scrypt().

   {
   scrypt(output, output_len,
          password, password_len,
          salt, salt_len,
          N(), r(), p());
   }

iterations()

size_t Botan::Scrypt::iterations ( ) const

inlineoverridevirtual

Most password hashes have some notion of iterations.

Implements Botan::PasswordHash.

Definition at line 41 of file scrypt.h.

{ return r(); }

memory_param()

size_t Botan::Scrypt::memory_param ( ) const

inlineoverridevirtual

Some password hashing algorithms have a parameter which controls how much memory is used. If not supported by some algorithm, returns 0.

Reimplemented from Botan::PasswordHash.

Definition at line 45 of file scrypt.h.

{ return N(); }

N()

size_t Botan::Scrypt::N ( ) const

inline

Definition at line 37 of file scrypt.h.

Referenced by derive_key().

{ return m_N; }

operator=()

Scrypt& Botan::Scrypt::operator= ( const Scrypt &  )

default

p()

size_t Botan::Scrypt::p ( ) const

inline

Definition at line 39 of file scrypt.h.

Referenced by derive_key().

{ return m_p; }

parallelism()

size_t Botan::Scrypt::parallelism ( ) const

inlineoverridevirtual

Some password hashing algorithms have a parallelism parameter. If the algorithm does not support this notion, then the function returns zero. This allows distinguishing between a password hash which just does not support parallel operation, vs one that does support parallel operation but which has been configured to use a single lane.

Reimplemented from Botan::PasswordHash.

Definition at line 43 of file scrypt.h.

{ return p(); }

r()

size_t Botan::Scrypt::r ( ) const

inline

Definition at line 38 of file scrypt.h.

Referenced by derive_key().

{ return m_r; }

to_string()

std::string Botan::Scrypt::to_string ( ) const

overridevirtual

Implements Botan::PasswordHash.

Definition at line 141 of file scrypt.cpp.

   {
   std::ostringstream oss;
   oss << "Scrypt(" << m_N << "," << m_r << "," << m_p << ")";
   return oss.str();
   }

total_memory_usage()

size_t Botan::Scrypt::total_memory_usage ( ) const

overridevirtual

Returns an estimate of the total memory usage required to perform this key derivation.

If this algorithm uses a small and constant amount of memory, with no effort made towards being memory hard, this function returns 0.

Reimplemented from Botan::PasswordHash.

Definition at line 148 of file scrypt.cpp.

References Botan::scrypt_memory_usage().

   {
   return scrypt_memory_usage(m_N, m_r, m_p);
   }

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

• src/lib/pbkdf/scrypt/scrypt.h
• src/lib/pbkdf/scrypt/scrypt.cpp