From b6c0cdbe7d20af48b0c2a909a66ff00b093d1542 Mon Sep 17 00:00:00 2001
From: Ken MacKay <kmackay@gmail.com>
Date: Tue, 8 Mar 2016 21:29:40 -0800
Subject: [PATCH] Add functions to get the private/public key size for a curve
 (#73)

---
 uECC.c |  8 ++++++++
 uECC.h | 12 ++++++++++++
 2 files changed, 20 insertions(+)

diff --git a/uECC.c b/uECC.c
index 63ec6f9..7717533 100644
--- a/uECC.c
+++ b/uECC.c
@@ -195,6 +195,14 @@ uECC_RNG_Function uECC_get_rng(void) {
     return g_rng_function;
 }
 
+int uECC_curve_private_key_size(uECC_Curve curve) {
+    return BITS_TO_BYTES(curve->num_n_bits);
+}
+
+int uECC_curve_public_key_size(uECC_Curve curve) {
+    return 2 * curve->num_bytes;
+}
+
 #if !asm_clear
 uECC_VLI_API void uECC_vli_clear(uECC_word_t *vli, wordcount_t num_words) {
     wordcount_t i;
diff --git a/uECC.h b/uECC.h
index dcc8e82..1193ce8 100644
--- a/uECC.h
+++ b/uECC.h
@@ -130,6 +130,18 @@ Returns the function that will be used to generate random bytes.
 */
 uECC_RNG_Function uECC_get_rng(void);
 
+/* uECC_curve_private_key_size() function.
+
+Returns the size of a private key for the curve in bytes.
+*/
+int uECC_curve_private_key_size(uECC_Curve curve);
+
+/* uECC_curve_public_key_size() function.
+
+Returns the size of a public key for the curve in bytes.
+*/
+int uECC_curve_public_key_size(uECC_Curve curve);
+
 /* uECC_make_key() function.
 Create a public/private key pair.