Minor changes to `custom_generator_test`:
- this is to align to the 1.1.1 version of the test (simplify the code
as there is no need to use `EC_GROUP_get_field_type()`)
- add comment to explain how the buffer size is computed
Reviewed-by: Matt Caswell <matt@openssl.org>
Reviewed-by: Paul Dale <paul.dale@oracle.com>
(Merged from https://github.com/openssl/openssl/pull/12507)
goto err;
/* expected byte length of encoded points */
- bsize = (EC_GROUP_get_field_type(group) == NID_X9_62_prime_field) ?
- BN_num_bytes(EC_GROUP_get0_field(group)) :
- (EC_GROUP_get_degree(group) + 7) / 8;
- bsize = 2 * bsize + 1;
+ bsize = (EC_GROUP_get_degree(group) + 7) / 8;
+ bsize = 1 + 2 * bsize; /* UNCOMPRESSED_POINT format */
if (!TEST_ptr(k = BN_CTX_get(ctx))
/* fetch a testing scalar k != 0,1 */