/* 
   Unix SMB/CIFS implementation.
   Copyright (C) Jelmer Vernooij <jelmer@samba.org> 2007-2008
   Copyright (C) Andrew Bartlett <abartlet@samba.org> 2011

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 3 of the License, or
   (at your option) any later version.
   
   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.
   
   You should have received a copy of the GNU General Public License
   along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/

#include <Python.h>
#include "includes.h"
#include "libcli/util/pyerrors.h"
#include "param/param.h"
#include "pyauth.h"
#include "pyldb.h"
#include "auth/system_session_proto.h"
#include "auth/auth.h"
#include "param/pyparam.h"
#include "libcli/security/security.h"
#include "auth/credentials/pycredentials.h"
#include "librpc/rpc/pyrpc_util.h"

static PyObject *py_auth_session_get_security_token(PyObject *self, void *closure)
{
	struct auth_session_info *session = py_talloc_get_type(self, struct auth_session_info);
	PyObject *py_security_token;
	py_security_token = py_return_ndr_struct("samba.dcerpc.security", "token",
						 session->security_token, session->security_token);
	return py_security_token;
}

static int py_auth_session_set_security_token(PyObject *self, PyObject *value, void *closure)
{
	struct auth_session_info *session = py_talloc_get_type(self, struct auth_session_info);
	session->security_token = talloc_reference(session, py_talloc_get_ptr(value));
	return 0;
}

static PyObject *py_auth_session_get_session_key(PyObject *self, void *closure)
{
	struct auth_session_info *session = py_talloc_get_type(self, struct auth_session_info);
	return PyString_FromStringAndSize((char *)session->session_key.data, session->session_key.length);
}

static int py_auth_session_set_session_key(PyObject *self, PyObject *value, void *closure)
{
	DATA_BLOB val;
	struct auth_session_info *session = py_talloc_get_type(self, struct auth_session_info);
	val.data = (uint8_t *)PyString_AsString(value);
	val.length = PyString_Size(value);

	session->session_key = data_blob_talloc(session, val.data, val.length);
	return 0;
}

static PyObject *py_auth_session_get_credentials(PyObject *self, void *closure)
{
	struct auth_session_info *session = py_talloc_get_type(self, struct auth_session_info);
	PyObject *py_credentials;
	/* This is evil, as the credentials are not IDL structures */
	py_credentials = py_return_ndr_struct("samba.credentials", "Credentials", session->credentials, session->credentials);
	return py_credentials;
}

static int py_auth_session_set_credentials(PyObject *self, PyObject *value, void *closure)
{
	struct auth_session_info *session = py_talloc_get_type(self, struct auth_session_info);
	session->credentials = talloc_reference(session, PyCredentials_AsCliCredentials(value));
	return 0;
}

static PyGetSetDef py_auth_session_getset[] = {
	{ discard_const_p(char, "security_token"), (getter)py_auth_session_get_security_token, (setter)py_auth_session_set_security_token, NULL },
	{ discard_const_p(char, "session_key"), (getter)py_auth_session_get_session_key, (setter)py_auth_session_set_session_key, NULL },
	{ discard_const_p(char, "credentials"), (getter)py_auth_session_get_credentials, (setter)py_auth_session_set_credentials, NULL },
	{ NULL }
};

static PyTypeObject PyAuthSession = {
	.tp_name = "AuthSession",
	.tp_basicsize = sizeof(py_talloc_Object),
	.tp_flags = Py_TPFLAGS_DEFAULT,
	.tp_getset = py_auth_session_getset,
};

PyObject *PyAuthSession_FromSession(struct auth_session_info *session)
{
	return py_talloc_reference(&PyAuthSession, session);
}

static PyObject *py_system_session(PyObject *module, PyObject *args)
{
	PyObject *py_lp_ctx = Py_None;
	struct loadparm_context *lp_ctx = NULL;
	struct auth_session_info *session;
	TALLOC_CTX *mem_ctx;
	if (!PyArg_ParseTuple(args, "|O", &py_lp_ctx))
		return NULL;

	mem_ctx = talloc_new(NULL);
	if (mem_ctx == NULL) {
		PyErr_NoMemory();
		return NULL;
	}

	lp_ctx = lpcfg_from_py_object(mem_ctx, py_lp_ctx);
	if (lp_ctx == NULL) {
		talloc_free(mem_ctx);
		return NULL;
	}

	session = system_session(lp_ctx);

	talloc_free(mem_ctx);

	return PyAuthSession_FromSession(session);
}


static PyObject *py_admin_session(PyObject *module, PyObject *args)
{
	PyObject *py_lp_ctx;
	PyObject *py_sid;
	struct loadparm_context *lp_ctx = NULL;
	struct auth_session_info *session;
	struct dom_sid *domain_sid = NULL;
	TALLOC_CTX *mem_ctx;

	if (!PyArg_ParseTuple(args, "OO", &py_lp_ctx, &py_sid))
		return NULL;

	mem_ctx = talloc_new(NULL);
	if (mem_ctx == NULL) {
		PyErr_NoMemory();
		return NULL;
	}

	lp_ctx = lpcfg_from_py_object(mem_ctx, py_lp_ctx);
	if (lp_ctx == NULL) {
		talloc_free(mem_ctx);
		return NULL;
	}

	domain_sid = dom_sid_parse_talloc(mem_ctx, PyString_AsString(py_sid));
	if (domain_sid == NULL) {
		PyErr_Format(PyExc_RuntimeError, "Unable to parse sid %s", 
					 PyString_AsString(py_sid));
		talloc_free(mem_ctx);
		return NULL;
	}
	session = admin_session(NULL, lp_ctx, domain_sid);
	talloc_free(mem_ctx);

	return PyAuthSession_FromSession(session);
}

static PyObject *py_user_session(PyObject *module, PyObject *args, PyObject *kwargs)
{
	NTSTATUS nt_status;
	struct auth_session_info *session;
	TALLOC_CTX *mem_ctx;
	const char * const kwnames[] = { "ldb", "lp_ctx", "principal", "dn", "session_info_flags", NULL };
	struct ldb_context *ldb_ctx;
	PyObject *py_ldb = Py_None;
	PyObject *py_dn = Py_None;
	PyObject *py_lp_ctx = Py_None;
	struct loadparm_context *lp_ctx = NULL;
	struct ldb_dn *user_dn;
	char *principal = NULL;
	int session_info_flags = 0; /* This is an int, because that's
				 * what we need for the python
				 * PyArg_ParseTupleAndKeywords */

	if (!PyArg_ParseTupleAndKeywords(args, kwargs, "O|OzOi",
					 discard_const_p(char *, kwnames),
					 &py_ldb, &py_lp_ctx, &principal, &py_dn, &session_info_flags)) {
		return NULL;
	}

	mem_ctx = talloc_new(NULL);
	if (mem_ctx == NULL) {
		PyErr_NoMemory();
		return NULL;
	}

	ldb_ctx = PyLdb_AsLdbContext(py_ldb);

	if (py_dn == Py_None) {
		user_dn = NULL;
	} else {
		if (!PyObject_AsDn(ldb_ctx, py_dn, ldb_ctx, &user_dn)) {
			talloc_free(mem_ctx);
			return NULL;
		}
	}

	lp_ctx = lpcfg_from_py_object(mem_ctx, py_lp_ctx);
	if (lp_ctx == NULL) {
		talloc_free(mem_ctx);
		return NULL;
	}

	nt_status = authsam_get_session_info_principal(mem_ctx, lp_ctx, ldb_ctx, principal, user_dn,
						       session_info_flags, &session);
	if (!NT_STATUS_IS_OK(nt_status)) {
		talloc_free(mem_ctx);
		PyErr_NTSTATUS_IS_ERR_RAISE(nt_status);
	}

	talloc_steal(NULL, session);
	talloc_free(mem_ctx);

	return PyAuthSession_FromSession(session);
}

static PyMethodDef py_auth_methods[] = {
	{ "system_session", (PyCFunction)py_system_session, METH_VARARGS, NULL },
	{ "admin_session", (PyCFunction)py_admin_session, METH_VARARGS, NULL },
	{ "user_session", (PyCFunction)py_user_session, METH_VARARGS|METH_KEYWORDS, NULL },
	{ NULL },
};

void initauth(void)
{
	PyObject *m;

	PyAuthSession.tp_base = PyTalloc_GetObjectType();
	if (PyAuthSession.tp_base == NULL)
		return;

	if (PyType_Ready(&PyAuthSession) < 0)
		return;

	m = Py_InitModule3("auth", py_auth_methods,
					   "Authentication and authorization support.");
	if (m == NULL)
		return;

	Py_INCREF(&PyAuthSession);
	PyModule_AddObject(m, "AuthSession", (PyObject *)&PyAuthSession);

#define ADD_FLAG(val)  PyModule_AddObject(m, #val, PyInt_FromLong(val))
	ADD_FLAG(AUTH_SESSION_INFO_DEFAULT_GROUPS);
	ADD_FLAG(AUTH_SESSION_INFO_AUTHENTICATED);
	ADD_FLAG(AUTH_SESSION_INFO_SIMPLE_PRIVILEGES);

}