aboutsummaryrefslogtreecommitdiff
path: root/crypto/ansi_cprng.c
diff options
context:
space:
mode:
Diffstat (limited to 'crypto/ansi_cprng.c')
-rw-r--r--crypto/ansi_cprng.c16
1 files changed, 13 insertions, 3 deletions
diff --git a/crypto/ansi_cprng.c b/crypto/ansi_cprng.c
index 72db0fd763c..486aa93646f 100644
--- a/crypto/ansi_cprng.c
+++ b/crypto/ansi_cprng.c
@@ -349,15 +349,25 @@ static int cprng_get_random(struct crypto_rng *tfm, u8 *rdata,
return get_prng_bytes(rdata, dlen, prng);
}
+/*
+ * This is the cprng_registered reset method the seed value is
+ * interpreted as the tuple { V KEY DT}
+ * V and KEY are required during reset, and DT is optional, detected
+ * as being present by testing the length of the seed
+ */
static int cprng_reset(struct crypto_rng *tfm, u8 *seed, unsigned int slen)
{
struct prng_context *prng = crypto_rng_ctx(tfm);
- u8 *key = seed + DEFAULT_PRNG_KSZ;
+ u8 *key = seed + DEFAULT_BLK_SZ;
+ u8 *dt = NULL;
if (slen < DEFAULT_PRNG_KSZ + DEFAULT_BLK_SZ)
return -EINVAL;
- reset_prng_context(prng, key, DEFAULT_PRNG_KSZ, seed, NULL);
+ if (slen >= (2 * DEFAULT_BLK_SZ + DEFAULT_PRNG_KSZ))
+ dt = key + DEFAULT_PRNG_KSZ;
+
+ reset_prng_context(prng, key, DEFAULT_PRNG_KSZ, seed, dt);
if (prng->flags & PRNG_NEED_RESET)
return -EINVAL;
@@ -379,7 +389,7 @@ static struct crypto_alg rng_alg = {
.rng = {
.rng_make_random = cprng_get_random,
.rng_reset = cprng_reset,
- .seedsize = DEFAULT_PRNG_KSZ + DEFAULT_BLK_SZ,
+ .seedsize = DEFAULT_PRNG_KSZ + 2*DEFAULT_BLK_SZ,
}
}
};