Only zeroise sensitive parts of DRBG context, so the type and flags

are undisturbed.

Allow setting of "rand" callbacks for DRBG.

fips/rand/fips_drbg_lib.c

@@ -114,7 +114,7 @@ void FIPS_drbg_free(DRBG_CTX *dctx)
 	{
 	if (dctx->uninstantiate)
 		dctx->uninstantiate(dctx);
-	OPENSSL_cleanse(dctx, sizeof(DRBG_CTX));
+	OPENSSL_cleanse(&dctx->d, sizeof(dctx->d));
 	OPENSSL_free(dctx);
 	}
 
@@ -403,7 +403,8 @@ int FIPS_drbg_uninstantiate(DRBG_CTX *dctx)
 	/* Although we'd like to cleanse here we can't because we have to
 	 * test the uninstantiate really zeroes the data.
 	 */
-	memset(dctx, 0, sizeof(DRBG_CTX));
+	memset(&dctx->d, 0, sizeof(dctx->d));
+	dctx->status = DRBG_STATUS_UNINITIALISED;
 	/* If method has problems uninstantiating, return error */
 	return rv;
 	}
@@ -425,6 +426,22 @@ int FIPS_drbg_set_callbacks(DRBG_CTX *dctx,
 	return 1;
 	}
 
+int FIPS_drbg_set_rand_callbacks(DRBG_CTX *dctx,
+	size_t (*get_adin)(DRBG_CTX *ctx, unsigned char **pout),
+	void (*cleanup_adin)(DRBG_CTX *ctx, unsigned char *out, size_t olen),
+	int (*rand_seed_cb)(DRBG_CTX *ctx, const void *buf, int num),
+	int (*rand_add_cb)(DRBG_CTX *ctx,
+				const void *buf, int num, double entropy))
+	{
+	if (dctx->status != DRBG_STATUS_UNINITIALISED)
+		return 0;
+	dctx->get_adin = get_adin;
+	dctx->cleanup_adin = cleanup_adin;
+	dctx->rand_seed_cb = rand_seed_cb;
+	dctx->rand_add_cb = rand_add_cb;
+	return 1;
+	}
+
 void *FIPS_drbg_get_app_data(DRBG_CTX *dctx)
 	{
 	return dctx->app_data;

fips/rand/fips_drbg_selftest.c

@@ -954,11 +954,11 @@ static int fips_drbg_health_check(DRBG_CTX *dctx, DRBG_SELFTEST_DATA *td)
 		}
 
 	FIPS_drbg_uninstantiate(dctx);
-	p = (unsigned char *)dctx;
+	p = (unsigned char *)&dctx->d;
 	/* Standard says we have to check uninstantiate really zeroes
 	 * the data...
 	 */
-	for (i = 0; i < sizeof(DRBG_CTX); i++)
+	for (i = 0; i < sizeof(dctx->d); i++)
 		{
 		if (*p != 0)
 			{
@@ -980,7 +980,7 @@ static int fips_drbg_health_check(DRBG_CTX *dctx, DRBG_SELFTEST_DATA *td)
 	return 0;
 
 	}
-		
+
 
 int fips_drbg_kat(DRBG_CTX *dctx, int nid, unsigned int flags)
 	{

fips/rand/fips_rand.h

@@ -97,6 +97,13 @@ int FIPS_drbg_set_callbacks(DRBG_CTX *dctx,
 				int entropy, size_t min_len, size_t max_len),
 	void (*cleanup_nonce)(DRBG_CTX *ctx, unsigned char *out, size_t olen));
 
+int FIPS_drbg_set_rand_callbacks(DRBG_CTX *dctx,
+	size_t (*get_adin)(DRBG_CTX *ctx, unsigned char **pout),
+	void (*cleanup_adin)(DRBG_CTX *ctx, unsigned char *out, size_t olen),
+	int (*rand_seed_cb)(DRBG_CTX *ctx, const void *buf, int num),
+	int (*rand_add_cb)(DRBG_CTX *ctx,
+				const void *buf, int num, double entropy));
+
 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);