entropy.c File Reference

#include "polarssl/config.h"
#include "polarssl/entropy.h"
#include "polarssl/entropy_poll.h"

Include dependency graph for entropy.c:

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Defines
#define	ENTROPY_MAX_LOOP   256
	Maximum amount to loop before error.
Functions
void	entropy_init (entropy_context *ctx)
	Initialize the context.
void	entropy_free (entropy_context *ctx)
	Free the data in the context.
int	entropy_add_source (entropy_context *ctx, f_source_ptr f_source, void *p_source, size_t threshold)
	Adds an entropy source to poll.
static int	entropy_update (entropy_context *ctx, unsigned char source_id, const unsigned char *data, size_t len)
int	entropy_update_manual (entropy_context *ctx, const unsigned char *data, size_t len)
	Add data to the accumulator manually.
int	entropy_gather (entropy_context *ctx)
	Trigger an extra gather poll for the accumulator.
int	entropy_func (void *data, unsigned char *output, size_t len)
	Retrieve entropy from the accumulator (Max ENTROPY_BLOCK_SIZE) (Thread-safe if POLARSSL_THREADING_C is enabled).

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Define Documentation

#define ENTROPY_MAX_LOOP   256

Maximum amount to loop before error.

Definition at line 37 of file entropy.c.

Referenced by entropy_func().

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Function Documentation

int entropy_add_source	(	entropy_context *	ctx,
		f_source_ptr	f_source,
		void *	p_source,
		size_t	threshold
	)

Adds an entropy source to poll.

Parameters:

	ctx	Entropy context
	f_source	Entropy function
	p_source	Function data
	threshold	Minimum required from source before entropy is released ( with entropy_func() )

Returns:

0 if successful or POLARSSL_ERR_ENTROPY_MAX_SOURCES

Definition at line 79 of file entropy.c.

References ENTROPY_MAX_SOURCES, source_state::f_source, source_state::p_source, POLARSSL_ERR_ENTROPY_MAX_SOURCES, entropy_context::source, entropy_context::source_count, and source_state::threshold.

Referenced by entropy_init().

void entropy_free

(

entropy_context *

ctx

)

Free the data in the context.

Parameters:

ctx

Entropy context to free

Definition at line 71 of file entropy.c.

References polarssl_mutex_free.

int entropy_func	(	void *	data,
		unsigned char *	output,
		size_t	len
	)

Retrieve entropy from the accumulator (Max ENTROPY_BLOCK_SIZE) (Thread-safe if POLARSSL_THREADING_C is enabled).

Parameters:

	data	Entropy context
	output	Buffer to fill
	len	Length of buffer

Returns:

0 if successful, or POLARSSL_ERR_ENTROPY_SOURCE_FAILED

Definition at line 176 of file entropy.c.

References entropy_context::accumulator, ENTROPY_BLOCK_SIZE, entropy_gather(), ENTROPY_MAX_LOOP, POLARSSL_ERR_ENTROPY_SOURCE_FAILED, POLARSSL_ERR_THREADING_MUTEX_ERROR, polarssl_mutex_lock, polarssl_mutex_unlock, sha256(), sha256_finish(), sha256_starts(), sha256_update(), sha512(), sha512_finish(), sha512_starts(), sha512_update(), source_state::size, entropy_context::source, entropy_context::source_count, and source_state::threshold.

int entropy_gather

(

entropy_context *

ctx

)

Trigger an extra gather poll for the accumulator.

Parameters:

ctx

Entropy context

Returns:

0 if successful, or POLARSSL_ERR_ENTROPY_SOURCE_FAILED

Definition at line 142 of file entropy.c.

References ENTROPY_MAX_GATHER, entropy_update(), source_state::f_source, source_state::p_source, POLARSSL_ERR_ENTROPY_NO_SOURCES_DEFINED, source_state::size, entropy_context::source, and entropy_context::source_count.

Referenced by entropy_func().

void entropy_init

(

entropy_context *

ctx

)

Initialize the context.

Parameters:

ctx

Entropy context to initialize

Definition at line 39 of file entropy.c.

References entropy_add_source(), ENTROPY_MIN_HARDCLOCK, ENTROPY_MIN_HAVEGE, ENTROPY_MIN_PLATFORM, hardclock_poll(), havege_init(), platform_entropy_poll(), polarssl_mutex_init, sha256_starts(), and sha512_starts().

static int entropy_update	(	entropy_context *	ctx,
		unsigned char	source_id,
		const unsigned char *	data,
		size_t	len
	)			[static]

Definition at line 100 of file entropy.c.

References entropy_context::accumulator, ENTROPY_BLOCK_SIZE, sha256(), sha256_update(), sha512(), and sha512_update().

Referenced by entropy_gather(), and entropy_update_manual().

int entropy_update_manual	(	entropy_context *	ctx,
		const unsigned char *	data,
		size_t	len
	)

Add data to the accumulator manually.

Parameters:

	ctx	Entropy context
	data	Data to add
	len	Length of data

Returns:

0 if successful

Definition at line 133 of file entropy.c.

References ENTROPY_SOURCE_MANUAL, and entropy_update().