commit a6bfc45b6286e358ba83f7daa769e1e9012cc7bb
author David Benjamin <davidben@google.com> Tue Mar 06 20:21:28 2018 -0500
committer CQ bot account: commit-bot@chromium.org <commit-bot@chromium.org> Wed Mar 07 21:17:31 2018 +0000
tree 11d4a1032f39b92e733e3cefb078e9ed56b18aa0
parent d62fe6f3e83a97d7fd81726ca8c2c4b84a2b3eb5

Store EC_KEY's private key as an EC_SCALAR.

This isn't strictly necessary now that BIGNUMs are safe, but we get to
rely on type-system annotations from EC_SCALAR. Additionally,
EC_POINT_mul depends on BN_div, while the EC_SCALAR version does not.

Change-Id: I75e6967f3d35aef17278b94862f4e506baff5c23
Reviewed-on: https://boringssl-review.googlesource.com/26424
Reviewed-by: Steven Valdez <svaldez@google.com>
Commit-Queue: David Benjamin <davidben@google.com>
CQ-Verified: CQ bot account: commit-bot@chromium.org <commit-bot@chromium.org>

crypto/ecdh/ecdh.c

diff --git a/crypto/ecdh/ecdh.c b/crypto/ecdh/ecdh.c
index f38de2f..7634ba5 100644
--- a/crypto/ecdh/ecdh.c
+++ b/crypto/ecdh/ecdh.c
@@ -74,6 +74,7 @@
 #include <openssl/err.h>
 #include <openssl/mem.h>
 
+#include "../fipsmodule/ec/internal.h"
 #include "../internal.h"
 
 
@@ -81,11 +82,11 @@
                      const EC_KEY *priv_key,
                      void *(*kdf)(const void *in, size_t inlen, void *out,
                                   size_t *outlen)) {
-  const BIGNUM *const priv = EC_KEY_get0_private_key(priv_key);
-  if (priv == NULL) {
+  if (priv_key->priv_key == NULL) {
     OPENSSL_PUT_ERROR(ECDH, ECDH_R_NO_PRIVATE_VALUE);
     return -1;
   }
+  const EC_SCALAR *const priv = &priv_key->priv_key->scalar;
 
   BN_CTX *ctx = BN_CTX_new();
   if (ctx == NULL) {
@@ -104,7 +105,7 @@
     goto err;
   }
 
-  if (!EC_POINT_mul(group, tmp, NULL, pub_key, priv, ctx)) {
+  if (!ec_point_mul_scalar(group, tmp, NULL, pub_key, priv, ctx)) {
     OPENSSL_PUT_ERROR(ECDH, ECDH_R_POINT_ARITHMETIC_FAILURE);
     goto err;
   }