HSM: fix Engine init/free logics

After ENGINE_init(), there should be an ENGINE_finish(). Moreover,
an ENGINE_free() can be performed after ENGINE_init() in any cases.

No need to have both ENGINE_free() and ENGINE_finish():
doc: All functional references are released by calling ENGINE_finish()
(which removes the implicit structural reference as well).

Suggested-by: Jakub Zelenka <bukka@php.net>

Author: vjardin

ext/openssl/openssl.c

@@ -960,12 +960,12 @@ static ENGINE *php_openssl_make_pkcs11_engine(const bool warn) /* {{{ */
 		}
 	}
 	if (!ENGINE_init(engine)) {
-		ENGINE_free(engine);
 		if (warn)
 			php_error_docref(NULL, E_WARNING, "Cannot init PKCS11 engine");
 		php_openssl_store_errors();
 		return NULL;
 	}
+	ENGINE_free(engine);
 
 	return engine;
 }
@@ -1452,11 +1452,10 @@ X509 *php_openssl_x509_from_str(zend_string *cert_str) {
 			return NULL;
 
 		if (!ENGINE_ctrl_cmd(engine, "LOAD_CERT_CTRL", 0, &parms, NULL, force_login)) {
-			ENGINE_free(engine);
+			ENGINE_finish(engine);
 			php_openssl_store_errors();
 			return NULL;
 		}
-		ENGINE_free(engine);
 		ENGINE_finish(engine);
 		if (parms.cert == NULL) {
 			php_openssl_store_errors();
@@ -3642,7 +3641,6 @@ EVP_PKEY *php_openssl_pkey_from_zval(zval *val, int public_key, char *passphrase
 		if (public_key) {
 			if (engine) {
 				key = ENGINE_load_public_key(engine, Z_STRVAL_P(val), NULL, NULL);
-				ENGINE_free(engine);
 				ENGINE_finish(engine);
 				engine = NULL;
 			}
@@ -3671,7 +3669,6 @@ EVP_PKEY *php_openssl_pkey_from_zval(zval *val, int public_key, char *passphrase
 			/* we want the private key */
 			if (engine) {
 				key = ENGINE_load_private_key(engine, Z_STRVAL_P(val), NULL, NULL);
-				ENGINE_free(engine);
 				ENGINE_finish(engine);
 				engine = NULL;
 			} else {