param_cmp
int (*param_cmp)(const EVP_PKEY *a,
ameth->param_cmp = param_cmp;
if (a->ameth != NULL && a->ameth->param_cmp != NULL)
return a->ameth->param_cmp(a, b);
if (a->ameth->param_cmp != NULL) {
ret = a->ameth->param_cmp(a, b);
param_table = sk_X509_VERIFY_PARAM_new(param_cmp);
int (*param_cmp)(const EVP_PKEY *a, const EVP_PKEY *b);
int (*param_cmp)(const EVP_PKEY *a,