+static int generate_key(DH *dh);
+static int compute_key(unsigned char *key, const BIGNUM *pub_key, DH *dh);
+static int dh_bn_mod_exp(const DH *dh, BIGNUM *r,
+ const BIGNUM *a, const BIGNUM *p,
+ const BIGNUM *m, BN_CTX *ctx,
+ BN_MONT_CTX *m_ctx);
+static int dh_init(DH *dh);
+static int dh_finish(DH *dh);
+
+int DH_generate_key(DH *dh)
+ {
+ return ENGINE_get_DH(dh->engine)->generate_key(dh);
+ }
+
+int DH_compute_key(unsigned char *key, const BIGNUM *pub_key, DH *dh)
+ {
+ return ENGINE_get_DH(dh->engine)->compute_key(key, pub_key, dh);
+ }
+
+static DH_METHOD dh_ossl = {
+"OpenSSL DH Method",
+generate_key,
+compute_key,
+dh_bn_mod_exp,
+dh_init,
+dh_finish,
+0,
+NULL
+};
+
+const DH_METHOD *DH_OpenSSL(void)
+{
+ return &dh_ossl;
+}
+
+static int generate_key(DH *dh)