Remove group_clear_finish EC_GROUP hooks.

These are never called. Group parameters are not secret anyway. This is
a remnant of upstream's EC_GROUP_clear_free.

Change-Id: I23a4076eae8e4561abddbe74d0ba72641532f229
Reviewed-on: https://boringssl-review.googlesource.com/6823
Reviewed-by: Adam Langley <alangley@gmail.com>

crypto/ec/ec_montgomery.c

diff --git a/crypto/ec/ec_montgomery.c b/crypto/ec/ec_montgomery.c
index 1d4113d..62b0d7f 100644
--- a/crypto/ec/ec_montgomery.c
+++ b/crypto/ec/ec_montgomery.c
@@ -91,14 +91,6 @@
   ec_GFp_simple_group_finish(group);
 }
 
-void ec_GFp_mont_group_clear_finish(EC_GROUP *group) {
-  BN_MONT_CTX_free(group->mont);
-  group->mont = NULL;
-  BN_clear_free(group->one);
-  group->one = NULL;
-  ec_GFp_simple_group_clear_finish(group);
-}
-
 int ec_GFp_mont_group_copy(EC_GROUP *dest, const EC_GROUP *src) {
   BN_MONT_CTX_free(dest->mont);
   dest->mont = NULL;
@@ -263,7 +255,6 @@
   static const EC_METHOD ret = {
     ec_GFp_mont_group_init,
     ec_GFp_mont_group_finish,
-    ec_GFp_mont_group_clear_finish,
     ec_GFp_mont_group_copy,
     ec_GFp_mont_group_set_curve,
     ec_GFp_simple_point_get_affine_coordinates,

crypto/ec/internal.h

diff --git a/crypto/ec/internal.h b/crypto/ec/internal.h
index bcc0e37..d1132f5 100644
--- a/crypto/ec/internal.h
+++ b/crypto/ec/internal.h
@@ -80,10 +80,9 @@
 
 
 struct ec_method_st {
-  /* used by EC_GROUP_new, EC_GROUP_free, EC_GROUP_clear_free, EC_GROUP_copy: */
+  /* used by EC_GROUP_new, EC_GROUP_free, EC_GROUP_copy: */
   int (*group_init)(EC_GROUP *);
   void (*group_finish)(EC_GROUP *);
-  void (*group_clear_finish)(EC_GROUP *);
   int (*group_copy)(EC_GROUP *, const EC_GROUP *);
 
   /* used by EC_GROUP_set_curve_GFp, EC_GROUP_get_curve_GFp, */
@@ -180,7 +179,6 @@
 /* method functions in simple.c */
 int ec_GFp_simple_group_init(EC_GROUP *);
 void ec_GFp_simple_group_finish(EC_GROUP *);
-void ec_GFp_simple_group_clear_finish(EC_GROUP *);
 int ec_GFp_simple_group_copy(EC_GROUP *, const EC_GROUP *);
 int ec_GFp_simple_group_set_curve(EC_GROUP *, const BIGNUM *p, const BIGNUM *a,
                                   const BIGNUM *b, BN_CTX *);
@@ -232,7 +230,6 @@
 int ec_GFp_mont_group_set_curve(EC_GROUP *, const BIGNUM *p, const BIGNUM *a,
                                 const BIGNUM *b, BN_CTX *);
 void ec_GFp_mont_group_finish(EC_GROUP *);
-void ec_GFp_mont_group_clear_finish(EC_GROUP *);
 int ec_GFp_mont_group_copy(EC_GROUP *, const EC_GROUP *);
 int ec_GFp_mont_field_mul(const EC_GROUP *, BIGNUM *r, const BIGNUM *a,
                           const BIGNUM *b, BN_CTX *);

crypto/ec/p224-64.c

diff --git a/crypto/ec/p224-64.c b/crypto/ec/p224-64.c
index 8e93850..790b1e7 100644
--- a/crypto/ec/p224-64.c
+++ b/crypto/ec/p224-64.c
@@ -1288,7 +1288,6 @@
 const EC_METHOD *EC_GFp_nistp224_method(void) {
   static const EC_METHOD ret = {ec_GFp_nistp224_group_init,
                                 ec_GFp_simple_group_finish,
-                                ec_GFp_simple_group_clear_finish,
                                 ec_GFp_simple_group_copy,
                                 ec_GFp_nistp224_group_set_curve,
                                 ec_GFp_nistp224_point_get_affine_coordinates,

crypto/ec/p256-64.c

diff --git a/crypto/ec/p256-64.c b/crypto/ec/p256-64.c
index 29e9a20..a5b64f3 100644
--- a/crypto/ec/p256-64.c
+++ b/crypto/ec/p256-64.c
@@ -1862,7 +1862,6 @@
   static const EC_METHOD ret = {
       ec_GFp_nistp256_group_init,
       ec_GFp_simple_group_finish,
-      ec_GFp_simple_group_clear_finish,
       ec_GFp_simple_group_copy, ec_GFp_nistp256_group_set_curve,
       ec_GFp_nistp256_point_get_affine_coordinates,
       ec_GFp_nistp256_points_mul,

crypto/ec/p256-x86_64.c

diff --git a/crypto/ec/p256-x86_64.c b/crypto/ec/p256-x86_64.c
index 2972483..ca967b3 100644
--- a/crypto/ec/p256-x86_64.c
+++ b/crypto/ec/p256-x86_64.c
@@ -567,7 +567,6 @@
   static const EC_METHOD ret = {
       ec_GFp_mont_group_init,
       ec_GFp_mont_group_finish,
-      ec_GFp_mont_group_clear_finish,
       ec_GFp_mont_group_copy,
       ec_GFp_mont_group_set_curve,
       ecp_nistz256_get_affine,

crypto/ec/simple.c

diff --git a/crypto/ec/simple.c b/crypto/ec/simple.c
index cef0e94..354b1c7 100644
--- a/crypto/ec/simple.c
+++ b/crypto/ec/simple.c
@@ -102,12 +102,6 @@
   BN_free(&group->b);
 }
 
-void ec_GFp_simple_group_clear_finish(EC_GROUP *group) {
-  BN_clear_free(&group->field);
-  BN_clear_free(&group->a);
-  BN_clear_free(&group->b);
-}
-
 int ec_GFp_simple_group_copy(EC_GROUP *dest, const EC_GROUP *src) {
   if (!BN_copy(&dest->field, &src->field) ||
       !BN_copy(&dest->a, &src->a) ||