-/* fips/rand/fips_drbg_lib.c */
/* Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL
* project.
*/
#include <string.h>
#include <openssl/crypto.h>
-#include <openssl/evp.h>
-#include <openssl/aes.h>
#include <openssl/err.h>
#include <openssl/fips_rand.h>
#include "fips_rand_lcl.h"
int rv;
memset(dctx, 0, sizeof(DRBG_CTX));
dctx->status = DRBG_STATUS_UNINITIALISED;
- dctx->flags = flags;
+ dctx->xflags = flags;
dctx->type = type;
+ dctx->iflags = 0;
+ dctx->entropy_blocklen = 0;
+ dctx->health_check_cnt = 0;
+ dctx->health_check_interval = DRBG_HEALTH_INTERVAL;
+
rv = fips_drbg_hash_init(dctx);
if (rv == -2)
rv = fips_drbg_ctr_init(dctx);
+ if (rv == -2)
+ rv = fips_drbg_hmac_init(dctx);
+ if (rv == -2)
+ rv = fips_drbg_ec_init(dctx);
if (rv <= 0)
{
/* If not in test mode run selftests on DRBG of the same type */
- if (!(dctx->flags & DRBG_FLAG_TEST))
+ if (!(dctx->xflags & DRBG_FLAG_TEST))
{
- DRBG_CTX tctx;
- if (!fips_drbg_kat(&tctx, type, flags | DRBG_FLAG_TEST))
+ if (!FIPS_drbg_health_check(dctx))
{
FIPSerr(FIPS_F_FIPS_DRBG_INIT, FIPS_R_SELFTEST_FAILURE);
return 0;
DRBG_CTX *FIPS_drbg_new(int type, unsigned int flags)
{
- int rv;
DRBG_CTX *dctx;
dctx = OPENSSL_malloc(sizeof(DRBG_CTX));
if (!dctx)
FIPSerr(FIPS_F_FIPS_DRBG_NEW, ERR_R_MALLOC_FAILURE);
return NULL;
}
+
if (type == 0)
+ {
+ memset(dctx, 0, sizeof(DRBG_CTX));
+ dctx->type = 0;
+ dctx->status = DRBG_STATUS_UNINITIALISED;
return dctx;
- rv = FIPS_drbg_init(dctx, type, flags);
+ }
if (FIPS_drbg_init(dctx, type, flags) <= 0)
{
OPENSSL_free(dctx);
}
+static size_t fips_get_entropy(DRBG_CTX *dctx, unsigned char **pout,
+ int entropy, size_t min_len, size_t max_len)
+ {
+ unsigned char *tout, *p;
+ size_t bl = dctx->entropy_blocklen, rv;
+ if (dctx->xflags & DRBG_FLAG_TEST || !bl)
+ return dctx->get_entropy(dctx, pout, entropy, min_len, max_len);
+ rv = dctx->get_entropy(dctx, &tout, entropy + bl,
+ min_len + bl, max_len + bl);
+ *pout = tout + bl;
+ if (rv < (min_len + bl) || (rv % bl))
+ return 0;
+ /* Compare consecutive blocks for continuous PRNG test */
+ for (p = tout; p < tout + rv - bl; p += bl)
+ {
+ if (!memcmp(p, p + bl, bl))
+ {
+ FIPSerr(FIPS_F_FIPS_GET_ENTROPY, FIPS_R_ENTROPY_SOURCE_STUCK);
+ return 0;
+ }
+ }
+ rv -= bl;
+ if (rv > max_len)
+ return max_len;
+ return rv;
+ }
+
+static void fips_cleanup_entropy(DRBG_CTX *dctx,
+ unsigned char *out, size_t olen)
+ {
+ size_t bl;
+ if (dctx->xflags & DRBG_FLAG_TEST)
+ bl = 0;
+ else
+ bl = dctx->entropy_blocklen;
+ /* Call cleanup with original arguments */
+ dctx->cleanup_entropy(dctx, out - bl, olen + bl);
+ }
+
+
int FIPS_drbg_instantiate(DRBG_CTX *dctx,
const unsigned char *pers, size_t perslen)
{
dctx->status = DRBG_STATUS_ERROR;
- entlen = dctx->get_entropy(dctx, &entropy, dctx->strength,
+ entlen = fips_get_entropy(dctx, &entropy, dctx->strength,
dctx->min_entropy, dctx->max_entropy);
if (entlen < dctx->min_entropy || entlen > dctx->max_entropy)
dctx->status = DRBG_STATUS_READY;
- dctx->reseed_counter = 1;
+ if (!(dctx->iflags & DRBG_CUSTOM_RESEED))
+ dctx->reseed_counter = 1;
end:
if (entropy && dctx->cleanup_entropy)
- dctx->cleanup_entropy(dctx, entropy, entlen);
+ fips_cleanup_entropy(dctx, entropy, entlen);
if (nonce && dctx->cleanup_nonce)
dctx->cleanup_nonce(dctx, nonce, noncelen);
if (dctx->status == DRBG_STATUS_READY)
return 1;
- if (r && !(dctx->flags & DRBG_FLAG_NOERR))
+ if (r && !(dctx->iflags & DRBG_FLAG_NOERR))
FIPSerr(FIPS_F_FIPS_DRBG_INSTANTIATE, r);
return 0;
}
-int FIPS_drbg_reseed(DRBG_CTX *dctx,
- const unsigned char *adin, size_t adinlen)
+static int drbg_reseed(DRBG_CTX *dctx,
+ const unsigned char *adin, size_t adinlen, int hcheck)
{
unsigned char *entropy = NULL;
size_t entlen;
}
dctx->status = DRBG_STATUS_ERROR;
+ /* Peform health check on all reseed operations if not a prediction
+ * resistance request and not in test mode.
+ */
+ if (hcheck && !(dctx->xflags & DRBG_FLAG_TEST))
+ {
+ if (!FIPS_drbg_health_check(dctx))
+ {
+ r = FIPS_R_SELFTEST_FAILURE;
+ goto end;
+ }
+ }
- entlen = dctx->get_entropy(dctx, &entropy, dctx->strength,
+ entlen = fips_get_entropy(dctx, &entropy, dctx->strength,
dctx->min_entropy, dctx->max_entropy);
if (entlen < dctx->min_entropy || entlen > dctx->max_entropy)
goto end;
dctx->status = DRBG_STATUS_READY;
- dctx->reseed_counter = 1;
+ if (!(dctx->iflags & DRBG_CUSTOM_RESEED))
+ dctx->reseed_counter = 1;
end:
if (entropy && dctx->cleanup_entropy)
- dctx->cleanup_entropy(dctx, entropy, entlen);
+ fips_cleanup_entropy(dctx, entropy, entlen);
if (dctx->status == DRBG_STATUS_READY)
return 1;
- if (r && !(dctx->flags & DRBG_FLAG_NOERR))
+ if (r && !(dctx->iflags & DRBG_FLAG_NOERR))
FIPSerr(FIPS_F_FIPS_DRBG_RESEED, r);
return 0;
}
+int FIPS_drbg_reseed(DRBG_CTX *dctx,
+ const unsigned char *adin, size_t adinlen)
+ {
+ return drbg_reseed(dctx, adin, adinlen, 1);
+ }
+
+static int fips_drbg_check(DRBG_CTX *dctx)
+ {
+ if (dctx->xflags & DRBG_FLAG_TEST)
+ return 1;
+ dctx->health_check_cnt++;
+ if (dctx->health_check_cnt >= dctx->health_check_interval)
+ {
+ if (!FIPS_drbg_health_check(dctx))
+ {
+ FIPSerr(FIPS_F_FIPS_DRBG_CHECK, FIPS_R_SELFTEST_FAILURE);
+ return 0;
+ }
+ }
+ return 1;
+ }
int FIPS_drbg_generate(DRBG_CTX *dctx, unsigned char *out, size_t outlen,
- int strength, int prediction_resistance,
+ int prediction_resistance,
const unsigned char *adin, size_t adinlen)
{
int r = 0;
+ if (!fips_drbg_check(dctx))
+ return 0;
+
if (dctx->status != DRBG_STATUS_READY
&& dctx->status != DRBG_STATUS_RESEED)
{
return 0;
}
- if (strength > dctx->strength)
+ if (adinlen > dctx->max_adin)
{
- r = FIPS_R_INSUFFICIENT_SECURITY_STRENGTH;
+ r = FIPS_R_ADDITIONAL_INPUT_TOO_LONG;
goto end;
}
+ if (dctx->iflags & DRBG_CUSTOM_RESEED)
+ dctx->generate(dctx, NULL, outlen, NULL, 0);
+ else if (dctx->reseed_counter >= dctx->reseed_interval)
+ dctx->status = DRBG_STATUS_RESEED;
+
if (dctx->status == DRBG_STATUS_RESEED || prediction_resistance)
{
- if (!FIPS_drbg_reseed(dctx, adin, adinlen))
+ /* If prediction resistance request don't do health check */
+ int hcheck = prediction_resistance ? 0 : 1;
+
+ if (!drbg_reseed(dctx, adin, adinlen, hcheck))
{
r = FIPS_R_RESEED_ERROR;
goto end;
dctx->status = DRBG_STATUS_ERROR;
goto end;
}
- if (dctx->reseed_counter >= dctx->reseed_interval)
- dctx->status = DRBG_STATUS_RESEED;
- else
- dctx->reseed_counter++;
+ if (!(dctx->iflags & DRBG_CUSTOM_RESEED))
+ {
+ if (dctx->reseed_counter >= dctx->reseed_interval)
+ dctx->status = DRBG_STATUS_RESEED;
+ else
+ dctx->reseed_counter++;
+ }
end:
if (r)
{
- if (!(dctx->flags & DRBG_FLAG_NOERR))
+ if (!(dctx->iflags & DRBG_FLAG_NOERR))
FIPSerr(FIPS_F_FIPS_DRBG_GENERATE, r);
return 0;
}
size_t (*get_entropy)(DRBG_CTX *ctx, unsigned char **pout,
int entropy, size_t min_len, size_t max_len),
void (*cleanup_entropy)(DRBG_CTX *ctx, unsigned char *out, size_t olen),
+ size_t entropy_blocklen,
size_t (*get_nonce)(DRBG_CTX *ctx, unsigned char **pout,
int entropy, size_t min_len, size_t max_len),
void (*cleanup_nonce)(DRBG_CTX *ctx, unsigned char *out, size_t olen))
{
if (dctx->status != DRBG_STATUS_UNINITIALISED)
return 0;
+ dctx->entropy_blocklen = entropy_blocklen;
dctx->get_entropy = get_entropy;
dctx->cleanup_entropy = cleanup_entropy;
dctx->get_nonce = get_nonce;
return dctx->strength;
}
+void FIPS_drbg_set_check_interval(DRBG_CTX *dctx, int interval)
+ {
+ dctx->health_check_interval = interval;
+ }
+
+void FIPS_drbg_set_reseed_interval(DRBG_CTX *dctx, int interval)
+ {
+ dctx->reseed_interval = interval;
+ }
+
static int drbg_stick = 0;
void FIPS_drbg_stick(void)
int fips_drbg_cprng_test(DRBG_CTX *dctx, const unsigned char *out)
{
/* No CPRNG in test mode */
- if (dctx->flags & DRBG_FLAG_TEST)
+ if (dctx->xflags & DRBG_FLAG_TEST)
return 1;
/* Check block is valid: should never happen */
if (dctx->lb_valid == 0)