ffi_rng.cpp File Reference

#include <botan/ffi.h>
#include <botan/internal/ffi_util.h>
#include <botan/internal/ffi_rng.h>
#include <botan/system_rng.h>
#include <botan/auto_rng.h>

Go to the source code of this file.

Functions
int	botan_rng_add_entropy (botan_rng_t rng, const uint8_t *input, size_t len)
int	botan_rng_destroy (botan_rng_t rng)
int	botan_rng_get (botan_rng_t rng, uint8_t *out, size_t out_len)
int	botan_rng_init (botan_rng_t *rng_out, const char *rng_type)
int	botan_rng_reseed (botan_rng_t rng, size_t bits)
int	botan_rng_reseed_from_rng (botan_rng_t rng, botan_rng_t source_rng, size_t bits)

Function Documentation

int botan_rng_add_entropy	(	botan_rng_t	rng,
		const uint8_t *	entropy,
		size_t	entropy_len
	)

Add some seed material to a random number generator

Parameters

rng	rng object
entropy	the data to add
entropy_len	length of entropy buffer

Returns

0 on success, a negative value on failure

Definition at line 81 of file ffi_rng.cpp.

References Botan::RandomNumberGenerator::add_entropy(), and BOTAN_FFI_DO.

   {
   return BOTAN_FFI_DO(Botan::RandomNumberGenerator, rng, r, { r.add_entropy(input, len); });
   }

int botan_rng_destroy

(

botan_rng_t

rng

)

Frees all resources of the random number generator object

Parameters

rng	rng object

Returns

0 if success, error if invalid object handle

Definition at line 66 of file ffi_rng.cpp.

References BOTAN_FFI_CHECKED_DELETE.

   {
   return BOTAN_FFI_CHECKED_DELETE(rng);
   }

int botan_rng_get	(	botan_rng_t	rng,
		uint8_t *	out,
		size_t	out_len
	)

Get random bytes from a random number generator

Parameters

rng	rng object
out	output buffer of size out_len
out_len	number of requested bytes

Returns

0 on success, negative on failure

Definition at line 71 of file ffi_rng.cpp.

References BOTAN_FFI_DO, and Botan::RandomNumberGenerator::randomize().

   {
   return BOTAN_FFI_DO(Botan::RandomNumberGenerator, rng, r, { r.randomize(out, out_len); });
   }

int botan_rng_init	(	botan_rng_t *	rng,
		const char *	rng_type
	)

Initialize a random number generator object

Parameters

rng	rng object
rng_type	type of the rng, possible values: "system": system RNG "user": userspace RNG "user-threadsafe": userspace RNG, with internal locking "rdrand": directly read RDRAND Set rng_type to null to let the library choose some default.

Definition at line 21 of file ffi_rng.cpp.

References Botan::RDRAND_RNG::available(), BOTAN_FFI_ERROR_NOT_IMPLEMENTED, BOTAN_FFI_ERROR_NULL_POINTER, BOTAN_FFI_SUCCESS, and Botan_FFI::ffi_guard_thunk().

   {
   return ffi_guard_thunk(__func__, [=]() -> int {
      if(rng_out == nullptr)
         return BOTAN_FFI_ERROR_NULL_POINTER;

      const std::string rng_type_s(rng_type ? rng_type : "system");

      std::unique_ptr<Botan::RandomNumberGenerator> rng;

      if(rng_type_s == "system")
         {
         rng.reset(new Botan::System_RNG);
         }
      else if(rng_type_s == "user")
         {
         rng.reset(new Botan::AutoSeeded_RNG);
         }
      else if(rng_type_s == "null")
         {
         rng.reset(new Botan::Null_RNG);
         }
#if defined(BOTAN_HAS_RDRAND_RNG)
      else if(rng_type_s == "rdrand" && Botan::RDRAND_RNG::available())
         {
         rng.reset(new Botan::RDRAND_RNG);
         }
#endif
#if defined(BOTAN_TARGET_OS_HAS_THREADS)
      else if(rng_type_s == "user-threadsafe")
         {
         rng.reset(new Botan::Serialized_RNG(new Botan::AutoSeeded_RNG));
         }
#endif

      if(!rng)
         {
         return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
         }

      *rng_out = new botan_rng_struct(rng.release());
      return BOTAN_FFI_SUCCESS;
      });
   }

int botan_rng_reseed	(	botan_rng_t	rng,
		size_t	bits
	)

Reseed a random number generator Uses the System_RNG as a seed generator.

Parameters

rng	rng object
bits	number of bits to to reseed with

Returns

0 on success, a negative value on failure

Definition at line 76 of file ffi_rng.cpp.

References BOTAN_FFI_DO, Botan::RandomNumberGenerator::reseed_from_rng(), and Botan::system_rng().

   {
   return BOTAN_FFI_DO(Botan::RandomNumberGenerator, rng, r, { r.reseed_from_rng(Botan::system_rng(), bits); });
   }

int botan_rng_reseed_from_rng	(	botan_rng_t	rng,
		botan_rng_t	source_rng,
		size_t	bits
	)

Reseed a random number generator

Parameters

rng	rng object
source_rng	the rng that will be read from
bits	number of bits to to reseed with

Returns

0 on success, a negative value on failure

Definition at line 86 of file ffi_rng.cpp.

References BOTAN_FFI_DO, Botan::RandomNumberGenerator::reseed_from_rng(), and Botan_FFI::safe_get().

   {
   return BOTAN_FFI_DO(Botan::RandomNumberGenerator, rng, r, { r.reseed_from_rng(safe_get(source_rng), bits); });
   }