X-Git-Url: https://git.openssl.org/gitweb/?p=openssl.git;a=blobdiff_plain;f=fips%2Frand%2Ffips_drbg_lib.c;h=46f059d05806da31fbc69c2805ac14da100e00c8;hp=7a0a1070e2b21dd740125a1e3256a1ee4bed2ff6;hb=fdb65c836cfc0c36f0a491a8fe4255cd18a7bc3f;hpb=42bd0a6b3c73c71b69967503c0ee0a3598b52655

diff --git a/fips/rand/fips_drbg_lib.c b/fips/rand/fips_drbg_lib.c
index 7a0a1070e2..46f059d058 100644
--- a/fips/rand/fips_drbg_lib.c
+++ b/fips/rand/fips_drbg_lib.c
@@ -71,6 +71,10 @@ int FIPS_drbg_init(DRBG_CTX *dctx, int type, unsigned int flags)
 	dctx->flags = flags;
 	dctx->type = type;
 
+	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)
@@ -84,12 +88,23 @@ int FIPS_drbg_init(DRBG_CTX *dctx, int type, unsigned int flags)
 			FIPSerr(FIPS_F_FIPS_DRBG_INIT, FIPS_R_ERROR_INITIALISING_DRBG);
 		}
 
+	/* If not in test mode run selftests on DRBG of the same type */
+
+	if (!(dctx->flags & DRBG_FLAG_TEST))
+		{
+		DRBG_CTX tctx;
+		if (!fips_drbg_kat(&tctx, type, flags | DRBG_FLAG_TEST))
+			{
+			FIPSerr(FIPS_F_FIPS_DRBG_INIT, FIPS_R_SELFTEST_FAILURE);
+			return 0;
+			}
+		}
+
 	return rv;
 	}
 
 DRBG_CTX *FIPS_drbg_new(int type, unsigned int flags)
 	{
-	int rv;
 	DRBG_CTX *dctx;
 	dctx = OPENSSL_malloc(sizeof(DRBG_CTX));
 	if (!dctx)
@@ -99,7 +114,6 @@ DRBG_CTX *FIPS_drbg_new(int type, unsigned int flags)
 		}
 	if (type == 0)
 		return dctx;
-	rv = FIPS_drbg_init(dctx, type, flags);
 
 	if (FIPS_drbg_init(dctx, type, flags) <= 0)
 		{
@@ -118,6 +132,46 @@ void FIPS_drbg_free(DRBG_CTX *dctx)
 	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->flags & 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->flags & 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)
 	{
@@ -154,7 +208,7 @@ int FIPS_drbg_instantiate(DRBG_CTX *dctx,
 
 	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)
@@ -193,7 +247,7 @@ int FIPS_drbg_instantiate(DRBG_CTX *dctx,
 	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);
@@ -239,7 +293,7 @@ int FIPS_drbg_reseed(DRBG_CTX *dctx,
 
 	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)
@@ -256,7 +310,7 @@ int FIPS_drbg_reseed(DRBG_CTX *dctx,
 	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;
@@ -267,6 +321,24 @@ 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,
@@ -274,6 +346,9 @@ 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)
 		{
@@ -349,12 +424,14 @@ int FIPS_drbg_set_callbacks(DRBG_CTX *dctx,
 	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;
@@ -398,6 +475,11 @@ 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)
@@ -414,7 +496,7 @@ int fips_drbg_cprng_test(DRBG_CTX *dctx, const unsigned char *out)
 	/* Check block is valid: should never happen */
 	if (dctx->lb_valid == 0)
 		{
-		FIPSerr(FIPS_F_DRBG_CPRNG_TEST, FIPS_R_INTERNAL_ERROR);
+		FIPSerr(FIPS_F_FIPS_DRBG_CPRNG_TEST, FIPS_R_INTERNAL_ERROR);
 		fips_set_selftest_fail();
 		return 0;
 		}
@@ -423,7 +505,7 @@ int fips_drbg_cprng_test(DRBG_CTX *dctx, const unsigned char *out)
 	/* Check against last block: fail if match */
 	if (!memcmp(dctx->lb, out, dctx->blocklength))
 		{
-		FIPSerr(FIPS_F_DRBG_CPRNG_TEST, FIPS_R_DRBG_STUCK);
+		FIPSerr(FIPS_F_FIPS_DRBG_CPRNG_TEST, FIPS_R_DRBG_STUCK);
 		fips_set_selftest_fail();
 		return 0;
 		}