@@ -27,7 +27,9 @@ static int ecdh_set_secret(struct crypto_kpp *tfm, const void *buf,
unsigned int len)
{
struct ecdh_ctx *ctx = ecdh_get_ctx(tfm);
+ u64 priv[ECC_MAX_DIGITS];
struct ecdh params;
+ int ret = 0;
if (crypto_ecdh_decode_key(buf, len, ¶ms) < 0 ||
params.key_size > sizeof(u64) * ctx->ndigits)
@@ -40,13 +42,16 @@ static int ecdh_set_secret(struct crypto_kpp *tfm, const void *buf,
ctx->private_key);
memcpy(ctx->private_key, params.key, params.key_size);
+ ecc_swap_digits(ctx->private_key, priv, ctx->ndigits);
if (ecc_is_key_valid(ctx->curve_id, ctx->ndigits,
- ctx->private_key, params.key_size) < 0) {
+ priv, params.key_size) < 0) {
memzero_explicit(ctx->private_key, params.key_size);
- return -EINVAL;
+ ret = -EINVAL;
}
- return 0;
+ memzero_explicit(priv, sizeof(priv));
+
+ return ret;
}
static int ecdh_compute_value(struct kpp_request *req)
ecc_is_key_valid expects a key with the most significant digit in the last entry of the digit array. Currently ecdh_set_secret passes a reversed key to ecc_is_key_valid that then passes the rather simple test checking whether the private key is in range [2, n-3]. For all current ecdh- supported curves (NIST P192/256/384) the 'n' parameter is a rather large number, therefore easily passing this test. Throughout the ecdh and ecc codebase the variable 'priv' is used for a private_key holding the bytes in proper byte order. Therefore, introduce priv in ecdh_set_secret and copy the bytes from ctx->private_key into priv in proper byte order by using ecc_swap_digits. Pass priv to ecc_is_valid_key. Cc: Ard Biesheuvel <ardb@kernel.org> Cc: Salvatore Benedetto <salvatore.benedetto@intel.com> Signed-off-by: Stefan Berger <stefanb@linux.ibm.com> --- crypto/ecdh.c | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-)