Message& Message::reset() noexcept {
return clear_headers().clear_body();
}
int local_scan(int fd, uschar **return_text)
{
PyObject *user_dict;
PyObject *user_func;
PyObject *result;
PyObject *header_tuple;
PyObject *original_recipients;
PyObject *working_recipients;
if (!expy_enabled)
return LOCAL_SCAN_ACCEPT;
if (!Py_IsInitialized()) /* local_scan() may have already been run */
{
Py_Initialize();
ExPy_Header_Line.ob_type = &PyType_Type;
}
if (!expy_exim_dict)
{
PyObject *module = Py_InitModule(expy_exim_module, expy_exim_methods); /* Borrowed reference */
Py_INCREF(module); /* convert to New reference */
expy_exim_dict = PyModule_GetDict(module); /* Borrowed reference */
Py_INCREF(expy_exim_dict); /* convert to New reference */
}
if (!expy_user_module)
{
if (expy_path_add)
{
PyObject *sys_module;
PyObject *sys_dict;
PyObject *sys_path;
PyObject *add_value;
sys_module = PyImport_ImportModule("sys"); /* New Reference */
if (!sys_module)
{
PyErr_Clear();
*return_text = "Internal error, can't import Python sys module";
log_write(0, LOG_REJECT, "Couldn't import Python 'sys' module");
/* FIXME: write out an exception traceback if possible to Exim log */
return PYTHON_FAILURE_RETURN;
}
sys_dict = PyModule_GetDict(sys_module); /* Borrowed Reference, never fails */
sys_path = PyMapping_GetItemString(sys_dict, "path"); /* New reference */
if (!sys_path || (!PyList_Check(sys_path)))
{
PyErr_Clear(); /* in case sys_path was NULL, harmless otherwise */
*return_text = "Internal error, sys.path doesn't exist or isn't a list";
log_write(0, LOG_REJECT, "expy: Python sys.path doesn't exist or isn't a list");
/* FIXME: write out an exception traceback if possible to Exim log */
return PYTHON_FAILURE_RETURN;
}
add_value = PyString_FromString(expy_path_add); /* New reference */
if (!add_value)
{
PyErr_Clear();
log_write(0, LOG_PANIC, "expy: Failed to create Python string from [%s]", expy_path_add);
return PYTHON_FAILURE_RETURN;
}
if (PyList_Append(sys_path, add_value))
{
PyErr_Clear();
log_write(0, LOG_PANIC, "expy: Failed to append [%s] to Python sys.path", expy_path_add);
}
Py_DECREF(add_value);
Py_DECREF(sys_path);
Py_DECREF(sys_module);
}
expy_user_module = PyImport_ImportModule(expy_scan_module); /* New Reference */
if (!expy_user_module)
{
PyErr_Clear();
*return_text = "Internal error, can't import Python local_scan module";
log_write(0, LOG_REJECT, "Couldn't import Python '%s' module", expy_scan_module);
return PYTHON_FAILURE_RETURN;
}
}
user_dict = PyModule_GetDict(expy_user_module); /* Borrowed Reference, never fails */
user_func = PyMapping_GetItemString(user_dict, expy_scan_function); /* New reference */
if (!user_func)
{
PyErr_Clear();
*return_text = "Internal error, module doesn't have local_scan function";
log_write(0, LOG_REJECT, "Python %s module doesn't have a %s function", expy_scan_module, expy_scan_function);
return PYTHON_FAILURE_RETURN;
}
/* so far so good, prepare to run function */
/* Copy exim variables */
expy_dict_int("debug_selector", debug_selector);
expy_dict_int("host_checking", host_checking);
expy_dict_string("interface_address", interface_address);
expy_dict_int("interface_port", interface_port);
expy_dict_string("message_id", message_id);
expy_dict_string("received_protocol", received_protocol);
expy_dict_string("sender_address", sender_address);
expy_dict_string("sender_host_address", sender_host_address);
expy_dict_string("sender_host_authenticated", sender_host_authenticated);
expy_dict_string("sender_host_name", sender_host_name);
expy_dict_int("sender_host_port", sender_host_port);
expy_dict_int("fd", fd);
/* copy some constants */
expy_dict_int("LOG_MAIN", LOG_MAIN);
expy_dict_int("LOG_PANIC", LOG_PANIC);
expy_dict_int("LOG_REJECT", LOG_REJECT);
expy_dict_int("LOCAL_SCAN_ACCEPT", LOCAL_SCAN_ACCEPT);
expy_dict_int("LOCAL_SCAN_ACCEPT_FREEZE", LOCAL_SCAN_ACCEPT_FREEZE);
expy_dict_int("LOCAL_SCAN_ACCEPT_QUEUE", LOCAL_SCAN_ACCEPT_QUEUE);
expy_dict_int("LOCAL_SCAN_REJECT", LOCAL_SCAN_REJECT);
expy_dict_int("LOCAL_SCAN_REJECT_NOLOGHDR", LOCAL_SCAN_REJECT_NOLOGHDR);
expy_dict_int("LOCAL_SCAN_TEMPREJECT", LOCAL_SCAN_TEMPREJECT);
expy_dict_int("LOCAL_SCAN_TEMPREJECT_NOLOGHDR", LOCAL_SCAN_TEMPREJECT_NOLOGHDR);
expy_dict_int("MESSAGE_ID_LENGTH", MESSAGE_ID_LENGTH);
expy_dict_int("SPOOL_DATA_START_OFFSET", SPOOL_DATA_START_OFFSET);
expy_dict_int("D_v", D_v);
expy_dict_int("D_local_scan", D_local_scan);
/* set the headers */
header_tuple = get_headers();
PyDict_SetItemString(expy_exim_dict, "headers", header_tuple);
/*
* make list of recipients, give module a copy to work with in
* List format, but keep original tuple to compare against later
*/
original_recipients = get_recipients(); /* New reference */
working_recipients = PySequence_List(original_recipients); /* New reference */
PyDict_SetItemString(expy_exim_dict, "recipients", working_recipients);
Py_DECREF(working_recipients);
/* Try calling our function */
result = PyObject_CallFunction(user_func, NULL); /* New reference */
Py_DECREF(user_func); /* Don't need ref to function anymore */
/* Check for Python exception */
if (!result)
{
PyErr_Clear();
*return_text = "Internal error, local_scan function failed";
Py_DECREF(original_recipients);
clear_headers(header_tuple);
Py_DECREF(header_tuple);
return PYTHON_FAILURE_RETURN;
// FIXME: should write exception to exim log somehow
}
/* User code may have replaced recipient list, so re-get ref */
working_recipients = PyDict_GetItemString(expy_exim_dict, "recipients"); /* Borrowed reference */
Py_XINCREF(working_recipients); /* convert to New reference */
/*
* reconcile original recipient list with what's present after
* Python code is done
*/
if ((!working_recipients) || (!PySequence_Check(working_recipients)) || (PySequence_Size(working_recipients) == 0))
/* Python code either deleted exim.recipients alltogether, or replaced
it with a non-list, or emptied out the list */
recipients_count = 0;
else
{
int i;
/* remove original recipients not on the working list, reverse order important! */
for (i = recipients_count - 1; i >= 0; i--)
{
PyObject *addr = PyTuple_GET_ITEM(original_recipients, i); /* borrowed ref */
if (!PySequence_Contains(working_recipients, addr))
expy_remove_recipient(i);
}
/* add new recipients not in the original list */
for (i = PySequence_Size(working_recipients) - 1; i >= 0; i--)
{
PyObject *addr = PySequence_GetItem(working_recipients, i);
if (!PySequence_Contains(original_recipients, addr))
receive_add_recipient(PyString_AsString(addr), -1);
Py_DECREF(addr);
}
}
Py_XDECREF(working_recipients); /* No longer needed */
Py_DECREF(original_recipients); /* No longer needed */
clear_headers(header_tuple);
Py_DECREF(header_tuple); /* No longer needed */
/* Deal with the return value, first see if python returned a non-empty sequence */
if (PySequence_Check(result) && (PySequence_Size(result) > 0))
{
/* save first item */
PyObject *rc = PySequence_GetItem(result, 0);
/* if more than one item, convert 2nd item to string and use as return text */
if (PySequence_Size(result) > 1)
{
PyObject *str;
PyObject *obj = PySequence_GetItem(result, 1); /* New reference */
str = PyObject_Str(obj); /* New reference */
*return_text = string_copy(PyString_AsString(str));
Py_DECREF(obj);
Py_DECREF(str);
}
/* drop the sequence, and focus on the first item we saved */
Py_DECREF(result);
result = rc;
}
/* If we have an integer, return that to Exim */
if (PyInt_Check(result))
{
int rc = PyInt_AsLong(result);
Py_DECREF(result);
return rc;
}
/* didn't return anything usable */
Py_DECREF(result);
*return_text = "Internal error, bad return code";
log_write(0, LOG_REJECT, "Python %s.%s function didn't return integer", expy_scan_module, expy_scan_function);
return PYTHON_FAILURE_RETURN;
}
