shared/ecc: Make ecc_make_key() a stand alone API

And correct minor flaws in API descriptions

Change-Id: I0fd146cbc0c4bc0637a2c0dc894c6fed1209d30a
Signed-off-by: Amit Purwar <amit.purwar@samsung.com>

diff --git a/src/shared/ecc.c b/src/shared/ecc.c
index 15f6b8a..8149f1d 100755 (executable)
--- a/src/shared/ecc.c
+++ b/src/shared/ecc.c
@@ -883,20 +883,29 @@ bool ecc_make_public_key(const uint8_t private_key[32], uint8_t public_key[64])
 
 bool ecc_make_key(uint8_t public_key[64], uint8_t private_key[32])
 {
+       struct ecc_point pk;
        uint64_t priv[NUM_ECC_DIGITS];
        unsigned int tries = 0;
-       bool result = false;
 
-       for (tries = 0; !result && tries < MAX_TRIES; tries++) {
-               if (!get_random_number(priv))
+       do {
+               if (!get_random_number(priv) || (tries++ >= MAX_TRIES))
+                       return false;
+
+               if (vli_is_zero(priv))
                        continue;
 
-               ecc_native2bytes(priv, private_key);
+               /* Make sure the private key is in the range [1, n-1]. */
+               if (vli_cmp(curve_n, priv) != 1)
+                       continue;
 
-               result = ecc_make_public_key(private_key, public_key);
-       }
+               ecc_point_mult(&pk, &curve_g, priv, NULL, vli_num_bits(priv));
+       } while (ecc_point_is_zero(&pk));
 
-       return result;
+       ecc_native2bytes(priv, private_key);
+       ecc_native2bytes(pk.x, public_key);
+       ecc_native2bytes(pk.y, &public_key[32]);
+
+       return true;
 }
 
 bool ecc_valid_public_key(const uint8_t public_key[64])

diff --git a/src/shared/ecc.h b/src/shared/ecc.h
index a88e735..8c15e4e 100755 (executable)
--- a/src/shared/ecc.h
+++ b/src/shared/ecc.h
@@ -29,8 +29,10 @@
 
 /* Create a public key from a private key.
  *
+ * Inputs:
+ *     private_key - Your private key.
+ *
  * Outputs:
- *     private_key - Const private key
  *     public_key  - Will be filled in with the public key.
  *
  * Returns true if the public key was generated successfully, false