Commit 14264b19 authored by Dr. Stephen Henson's avatar Dr. Stephen Henson
Browse files

Add periodic DRBG health checks as required by SP800-90.

parent 8da18ea1

crypto/fips_err.h

+1 −0
Original line number Diff line number Diff line
@@ -82,6 +82,7 @@ static ERR_STRING_DATA FIPS_str_functs[]= 
{ERR_FUNC(FIPS_F_FIPS_CIPHERINIT),	"FIPS_CIPHERINIT"},

{ERR_FUNC(FIPS_F_FIPS_DIGESTINIT),	"FIPS_DIGESTINIT"},

{ERR_FUNC(FIPS_F_FIPS_DRBG_BYTES),	"FIPS_DRBG_BYTES"},

{ERR_FUNC(FIPS_F_FIPS_DRBG_CHECK),	"FIPS_DRBG_CHECK"},

{ERR_FUNC(FIPS_F_FIPS_DRBG_CPRNG_TEST),	"FIPS_DRBG_CPRNG_TEST"},

{ERR_FUNC(FIPS_F_FIPS_DRBG_GENERATE),	"FIPS_drbg_generate"},

{ERR_FUNC(FIPS_F_FIPS_DRBG_HEALTH_CHECK),	"FIPS_DRBG_HEALTH_CHECK"},

fips/fips.h

+1 −0
Original line number Diff line number Diff line
@@ -244,6 +244,7 @@ void ERR_load_FIPS_strings(void); 
#define FIPS_F_FIPS_CIPHERINIT				 109

#define FIPS_F_FIPS_DIGESTINIT				 110

#define FIPS_F_FIPS_DRBG_BYTES				 111

#define FIPS_F_FIPS_DRBG_CHECK				 146

#define FIPS_F_FIPS_DRBG_CPRNG_TEST			 112

#define FIPS_F_FIPS_DRBG_GENERATE			 113

#define FIPS_F_FIPS_DRBG_HEALTH_CHECK			 114

fips/rand/fips_drbg_lib.c

+29 −0
Original line number Diff line number Diff line
@@ -71,6 +71,9 @@ int FIPS_drbg_init(DRBG_CTX *dctx, int type, unsigned int flags) 
	dctx->flags = flags;

	dctx->type = type;



	dctx->health_check_cnt = 0;

	dctx->health_check_interval = DRBG_HEALTH_INTERVAL;



	rv = fips_drbg_hash_init(dctx);



	if (rv == -2)
@@ -277,6 +280,24 @@ int FIPS_drbg_reseed(DRBG_CTX *dctx, 
	return 0;

	}



static int fips_drbg_check(DRBG_CTX *dctx)

	{

	if (dctx->flags & DRBG_FLAG_TEST)

		return 1;

	dctx->health_check_cnt++;

	if (dctx->health_check_cnt >= dctx->health_check_interval)

		{

		DRBG_CTX tctx;

		if (!fips_drbg_kat(&tctx, dctx->type,

						dctx->flags | DRBG_FLAG_TEST))

			{

			FIPSerr(FIPS_F_FIPS_DRBG_CHECK, FIPS_R_SELFTEST_FAILURE);

			return 0;

			}

		dctx->health_check_cnt = 0;

		}

	return 1;

	}



int FIPS_drbg_generate(DRBG_CTX *dctx, unsigned char *out, size_t outlen,

			int strength, int prediction_resistance,
@@ -284,6 +305,9 @@ int FIPS_drbg_generate(DRBG_CTX *dctx, unsigned char *out, size_t outlen, 
	{

	int r = 0;



	if (!fips_drbg_check(dctx))

		return 0;



	if (dctx->status != DRBG_STATUS_READY

		&& dctx->status != DRBG_STATUS_RESEED)

		{
@@ -408,6 +432,11 @@ int FIPS_drbg_get_strength(DRBG_CTX *dctx) 
	return dctx->strength;

	}



void FIPS_drbg_set_check_interval(DRBG_CTX *dctx, int interval)

	{

	dctx->health_check_interval = interval;

	}



static int drbg_stick = 0;



void FIPS_drbg_stick(void)

fips/rand/fips_rand.h

+1 −0
Original line number Diff line number Diff line
@@ -108,6 +108,7 @@ void *FIPS_drbg_get_app_data(DRBG_CTX *ctx); 
void FIPS_drbg_set_app_data(DRBG_CTX *ctx, void *app_data);

size_t FIPS_drbg_get_blocklength(DRBG_CTX *dctx);

int FIPS_drbg_get_strength(DRBG_CTX *dctx);

void FIPS_drbg_set_check_interval(DRBG_CTX *dctx, int interval);



DRBG_CTX *FIPS_get_default_drbg(void);

const RAND_METHOD *FIPS_drbg_method(void);

fips/rand/fips_rand_lcl.h

+4 −0
Original line number Diff line number Diff line
@@ -105,6 +105,8 @@ struct drbg_ctr_ctx_st 
 */

#define DRBG_MAX_BLOCK			EVP_MAX_MD_SIZE



#define DRBG_HEALTH_INTERVAL		(1 << 24)



/* DRBG context structure */



struct drbg_ctx_st
@@ -114,6 +116,8 @@ struct drbg_ctx_st 
	int type;

	/* Various flags */

	unsigned int flags;

	/* Used for periodic health checks */

	int health_check_cnt, health_check_interval;



	/* The following parameters are setup by mechanism drbg_init() call */

	int strength;