Use ECDH_size() instead of rolling our own.

ok beck@

1 files changed, 5 insertions, 6 deletions

diff --git a/src/lib/libssl/s3_clnt.c b/src/lib/libssl/s3_clnt.c
index c2f5ea4e07..e33d745b19 100644
--- a/src/lib/libssl/s3_clnt.c
+++ b/src/lib/libssl/s3_clnt.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: s3_clnt.c,v 1.133 2015/09/12 20:56:14 jsing Exp $ */
+/* $OpenBSD: s3_clnt.c,v 1.134 2015/09/13 12:39:16 jsing Exp $ */
 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
  * All rights reserved.
  *
@@ -1975,7 +1975,7 @@ ssl3_client_kex_ecdh(SSL *s, SESS_CERT *sess_cert, unsigned char *p,
         unsigned char *encodedPoint = NULL;
         unsigned long alg_k;
         int encoded_pt_len = 0;
-        int field_size = 0;
+        int key_size;
         EC_KEY *tkey;
         int ret = -1;
         int n;
@@ -2035,13 +2035,12 @@ ssl3_client_kex_ecdh(SSL *s, SESS_CERT *sess_cert, unsigned char *p,
          * Use the 'p' output buffer for the ECDH key, but make sure to clear
          * it out afterwards.
          */
-        field_size = EC_GROUP_get_degree(srvr_group);
-        if (field_size <= 0) {
+        key_size = ECDH_size(clnt_ecdh);
+        if (key_size <= 0) {
                 SSLerr(SSL_F_SSL3_SEND_CLIENT_KEY_EXCHANGE, ERR_R_ECDH_LIB);
                 goto err;
         }
-        n = ECDH_compute_key(p, (field_size + 7) / 8, srvr_ecpoint, clnt_ecdh,
-            NULL);
+        n = ECDH_compute_key(p, key_size, srvr_ecpoint, clnt_ecdh, NULL);
         if (n <= 0) {
                 SSLerr(SSL_F_SSL3_SEND_CLIENT_KEY_EXCHANGE, ERR_R_ECDH_LIB);
                 goto err;