1 files changed, 71 insertions, 22 deletions

diff --git a/crypto/ansi_cprng.c b/crypto/ansi_cprng.c
index 3aa6e3834bf..666f1962a16 100644
--- a/crypto/ansi_cprng.c
+++ b/crypto/ansi_cprng.c
@@ -83,9 +83,9 @@ static void xor_vectors(unsigned char *in1, unsigned char *in2,
 }
 /*
  * Returns DEFAULT_BLK_SZ bytes of random data per call
- * returns 0 if generation succeded, <0 if something went wrong
+ * returns 0 if generation succeeded, <0 if something went wrong
  */
-static int _get_more_prng_bytes(struct prng_context *ctx)
+static int _get_more_prng_bytes(struct prng_context *ctx, int cont_test)
 {
 	int i;
 	unsigned char tmp[DEFAULT_BLK_SZ];
@@ -132,7 +132,7 @@ static int _get_more_prng_bytes(struct prng_context *ctx)
 			 */
 			if (!memcmp(ctx->rand_data, ctx->last_rand_data,
 					DEFAULT_BLK_SZ)) {
-				if (fips_enabled) {
+				if (cont_test) {
 					panic("cprng %p Failed repetition check!\n",
 						ctx);
 				}
@@ -185,16 +185,14 @@ static int _get_more_prng_bytes(struct prng_context *ctx)
 }
 
 /* Our exported functions */
-static int get_prng_bytes(char *buf, size_t nbytes, struct prng_context *ctx)
+static int get_prng_bytes(char *buf, size_t nbytes, struct prng_context *ctx,
+				int do_cont_test)
 {
 	unsigned char *ptr = buf;
 	unsigned int byte_count = (unsigned int)nbytes;
 	int err;
 
 
-	if (nbytes < 0)
-		return -EINVAL;
-
 	spin_lock_bh(&ctx->prng_lock);
 
 	err = -EINVAL;
@@ -220,7 +218,7 @@ static int get_prng_bytes(char *buf, size_t nbytes, struct prng_context *ctx)
 
 remainder:
 	if (ctx->rand_data_valid == DEFAULT_BLK_SZ) {
-		if (_get_more_prng_bytes(ctx) < 0) {
+		if (_get_more_prng_bytes(ctx, do_cont_test) < 0) {
 			memset(buf, 0, nbytes);
 			err = -EINVAL;
 			goto done;
@@ -232,11 +230,11 @@ remainder:
 	 */
 	if (byte_count < DEFAULT_BLK_SZ) {
 empty_rbuf:
-		for (; ctx->rand_data_valid < DEFAULT_BLK_SZ;
-			ctx->rand_data_valid++) {
+		while (ctx->rand_data_valid < DEFAULT_BLK_SZ) {
 			*ptr = ctx->rand_data[ctx->rand_data_valid];
 			ptr++;
 			byte_count--;
+			ctx->rand_data_valid++;
 			if (byte_count == 0)
 				goto done;
 		}
@@ -247,7 +245,7 @@ empty_rbuf:
 	 */
 	for (; byte_count >= DEFAULT_BLK_SZ; byte_count -= DEFAULT_BLK_SZ) {
 		if (ctx->rand_data_valid == DEFAULT_BLK_SZ) {
-			if (_get_more_prng_bytes(ctx) < 0) {
+			if (_get_more_prng_bytes(ctx, do_cont_test) < 0) {
 				memset(buf, 0, nbytes);
 				err = -EINVAL;
 				goto done;
@@ -356,7 +354,7 @@ static int cprng_get_random(struct crypto_rng *tfm, u8 *rdata,
 {
 	struct prng_context *prng = crypto_rng_ctx(tfm);
 
-	return get_prng_bytes(rdata, dlen, prng);
+	return get_prng_bytes(rdata, dlen, prng, 0);
 }
 
 /*
@@ -384,7 +382,45 @@ static int cprng_reset(struct crypto_rng *tfm, u8 *seed, unsigned int slen)
 	return 0;
 }
 
-static struct crypto_alg rng_alg = {
+#ifdef CONFIG_CRYPTO_FIPS
+static int fips_cprng_get_random(struct crypto_rng *tfm, u8 *rdata,
+			    unsigned int dlen)
+{
+	struct prng_context *prng = crypto_rng_ctx(tfm);
+
+	return get_prng_bytes(rdata, dlen, prng, 1);
+}
+
+static int fips_cprng_reset(struct crypto_rng *tfm, u8 *seed, unsigned int slen)
+{
+	u8 rdata[DEFAULT_BLK_SZ];
+	u8 *key = seed + DEFAULT_BLK_SZ;
+	int rc;
+
+	struct prng_context *prng = crypto_rng_ctx(tfm);
+
+	if (slen < DEFAULT_PRNG_KSZ + DEFAULT_BLK_SZ)
+		return -EINVAL;
+
+	/* fips strictly requires seed != key */
+	if (!memcmp(seed, key, DEFAULT_PRNG_KSZ))
+		return -EINVAL;
+
+	rc = cprng_reset(tfm, seed, slen);
+
+	if (!rc)
+		goto out;
+
+	/* this primes our continuity test */
+	rc = get_prng_bytes(rdata, DEFAULT_BLK_SZ, prng, 0);
+	prng->rand_data_valid = DEFAULT_BLK_SZ;
+
+out:
+	return rc;
+}
+#endif
+
+static struct crypto_alg rng_algs[] = { {
 	.cra_name		= "stdrng",
 	.cra_driver_name	= "ansi_cprng",
 	.cra_priority		= 100,
@@ -392,7 +428,6 @@ static struct crypto_alg rng_alg = {
 	.cra_ctxsize		= sizeof(struct prng_context),
 	.cra_type		= &crypto_rng_type,
 	.cra_module		= THIS_MODULE,
-	.cra_list		= LIST_HEAD_INIT(rng_alg.cra_list),
 	.cra_init		= cprng_init,
 	.cra_exit		= cprng_exit,
 	.cra_u			= {
@@ -402,22 +437,36 @@ static struct crypto_alg rng_alg = {
 			.seedsize = DEFAULT_PRNG_KSZ + 2*DEFAULT_BLK_SZ,
 		}
 	}
-};
-
+#ifdef CONFIG_CRYPTO_FIPS
+}, {
+	.cra_name		= "fips(ansi_cprng)",
+	.cra_driver_name	= "fips_ansi_cprng",
+	.cra_priority		= 300,
+	.cra_flags		= CRYPTO_ALG_TYPE_RNG,
+	.cra_ctxsize		= sizeof(struct prng_context),
+	.cra_type		= &crypto_rng_type,
+	.cra_module		= THIS_MODULE,
+	.cra_init		= cprng_init,
+	.cra_exit		= cprng_exit,
+	.cra_u			= {
+		.rng = {
+			.rng_make_random	= fips_cprng_get_random,
+			.rng_reset		= fips_cprng_reset,
+			.seedsize = DEFAULT_PRNG_KSZ + 2*DEFAULT_BLK_SZ,
+		}
+	}
+#endif
+} };
 
 /* Module initalization */
 static int __init prng_mod_init(void)
 {
-	if (fips_enabled)
-		rng_alg.cra_priority += 200;
-
-	return crypto_register_alg(&rng_alg);
+	return crypto_register_algs(rng_algs, ARRAY_SIZE(rng_algs));
 }
 
 static void __exit prng_mod_fini(void)
 {
-	crypto_unregister_alg(&rng_alg);
-	return;
+	crypto_unregister_algs(rng_algs, ARRAY_SIZE(rng_algs));
 }
 
 MODULE_LICENSE("GPL");