Add CRYPTO_EX_DATA; remove EC_EXTRA_DATA

Add CRYPTO_EX_DATA add EndC_KEY_[gs]et_method, From Roumen Petrov.
Had to add various exdata calls to init/copy/free the exdata.
Had to remove const from some EC functions because exdata isn't
const-correct. :(
Also remove EC_EXTRA_DATA and use a union to hold the possible
pre-computed values and an enum to tell which value is in the
union. (Rich Salz)

Reviewed-by: Dr. Stephen Henson <steve@openssl.org>

1 files changed, 15 insertions, 54 deletions

diff --git a/crypto/ec/ecp_nistp521.c b/crypto/ec/ecp_nistp521.c
index dd5b19b581..97744b273e 100644
--- a/crypto/ec/ecp_nistp521.c
+++ b/crypto/ec/ecp_nistp521.c
@@ -1585,10 +1585,10 @@ static void batch_mul(felem x_out, felem y_out, felem z_out,
 }
 
 /* Precomputation for the group generator. */
-typedef struct {
+struct nistp512_pre_comp_st {
     felem g_pre_comp[16][3];
     int references;
-} NISTP521_PRE_COMP;
+};
 
 const EC_METHOD *EC_GFp_nistp521_method(void)
 {
@@ -1654,44 +1654,19 @@ static NISTP521_PRE_COMP *nistp521_pre_comp_new()
     return ret;
 }
 
-static void *nistp521_pre_comp_dup(void *src_)
+NISTP521_PRE_COMP *EC_nistp521_pre_comp_dup(NISTP521_PRE_COMP *p)
 {
-    NISTP521_PRE_COMP *src = src_;
-
-    /* no need to actually copy, these objects never change! */
-    CRYPTO_add(&src->references, 1, CRYPTO_LOCK_EC_PRE_COMP);
-
-    return src_;
+    if (p != NULL)
+        CRYPTO_add(&p->references, 1, CRYPTO_LOCK_EC_PRE_COMP);
+    return p;
 }
 
-static void nistp521_pre_comp_free(void *pre_)
+void EC_nistp521_pre_comp_free(NISTP521_PRE_COMP *p)
 {
-    int i;
-    NISTP521_PRE_COMP *pre = pre_;
-
-    if (!pre)
+    if (p == NULL
+            || CRYPTO_add(&p->references, -1, CRYPTO_LOCK_EC_PRE_COMP) > 0)
         return;
-
-    i = CRYPTO_add(&pre->references, -1, CRYPTO_LOCK_EC_PRE_COMP);
-    if (i > 0)
-        return;
-
-    OPENSSL_free(pre);
-}
-
-static void nistp521_pre_comp_clear_free(void *pre_)
-{
-    int i;
-    NISTP521_PRE_COMP *pre = pre_;
-
-    if (!pre)
-        return;
-
-    i = CRYPTO_add(&pre->references, -1, CRYPTO_LOCK_EC_PRE_COMP);
-    if (i > 0)
-        return;
-
-    OPENSSL_clear_free(pre, sizeof(*pre));
+    OPENSSL_free(p);
 }
 
 /******************************************************************************/
@@ -1858,10 +1833,7 @@ int ec_GFp_nistp521_points_mul(const EC_GROUP *group, EC_POINT *r,
         goto err;
 
     if (scalar != NULL) {
-        pre = EC_EX_DATA_get_data(group->extra_data,
-                                  nistp521_pre_comp_dup,
-                                  nistp521_pre_comp_free,
-                                  nistp521_pre_comp_clear_free);
+        pre = group->pre_comp.nistp521;
         if (pre)
             /* we have precomputation, try to use it */
             g_pre_comp = &pre->g_pre_comp[0];
@@ -2036,9 +2008,7 @@ int ec_GFp_nistp521_precompute_mult(EC_GROUP *group, BN_CTX *ctx)
     felem tmp_felems[16];
 
     /* throw away old precomputation */
-    EC_EX_DATA_free_data(&group->extra_data, nistp521_pre_comp_dup,
-                         nistp521_pre_comp_free,
-                         nistp521_pre_comp_clear_free);
+    EC_nistp521_pre_comp_free(group->pre_comp.nistp521);
     if (ctx == NULL)
         if ((ctx = new_ctx = BN_CTX_new()) == NULL)
             return 0;
@@ -2121,29 +2091,20 @@ int ec_GFp_nistp521_precompute_mult(EC_GROUP *group, BN_CTX *ctx)
     }
     make_points_affine(15, &(pre->g_pre_comp[1]), tmp_felems);
 
-    if (!EC_EX_DATA_set_data(&group->extra_data, pre, nistp521_pre_comp_dup,
-                             nistp521_pre_comp_free,
-                             nistp521_pre_comp_clear_free))
-        goto err;
+    SETPRECOMP(group, nistp521, pre);
     ret = 1;
     pre = NULL;
  err:
     BN_CTX_end(ctx);
     EC_POINT_free(generator);
     BN_CTX_free(new_ctx);
-    nistp521_pre_comp_free(pre);
+    EC_nistp521_pre_comp_free(pre);
     return ret;
 }
 
 int ec_GFp_nistp521_have_precompute_mult(const EC_GROUP *group)
 {
-    if (EC_EX_DATA_get_data(group->extra_data, nistp521_pre_comp_dup,
-                            nistp521_pre_comp_free,
-                            nistp521_pre_comp_clear_free)
-        != NULL)
-        return 1;
-    else
-        return 0;
+    return HAVEPRECOMP(group, nistp512);
 }
 
 #else