Source code

Revision control

Copy as Markdown

Other Tools

/*
* (C) 2016,2019,2020 Jack Lloyd
*
* Botan is released under the Simplified BSD License (see license.txt)
*/
#ifndef BOTAN_RNG_PROCESSOR_RNG_H_
#define BOTAN_RNG_PROCESSOR_RNG_H_
#include <botan/rng.h>
namespace Botan {
/**
* Directly invokes a CPU specific instruction to generate random numbers.
* On x86, the RDRAND instruction is used.
* on POWER, the DARN instruction is used.
*/
class BOTAN_PUBLIC_API(2,15) Processor_RNG final : public Hardware_RNG
{
public:
/**
* Constructor will throw if CPU does not have RDRAND bit set
*/
Processor_RNG();
/**
* Return true if RNG instruction is available on the current processor
*/
static bool available();
bool accepts_input() const override { return false; }
bool is_seeded() const override { return true; }
void randomize(uint8_t out[], size_t out_len) override;
/*
* No way to provide entropy to RDRAND generator, so add_entropy is ignored
*/
void add_entropy(const uint8_t[], size_t) override;
/*
* No way to reseed processor provided generator, so reseed is ignored
*/
size_t reseed(Entropy_Sources&, size_t, std::chrono::milliseconds) override;
std::string name() const override;
};
}
#endif