1 files changed, 85 insertions, 0 deletions
diff --git a/source4/kdc/authn_policy.c b/source4/kdc/authn_policy.c
new file mode 100644
index 00000000000..93892f58dbc
--- /dev/null
+++ b/source4/kdc/authn_policy.c
@@ -0,0 +1,85 @@
+/*
+   Unix SMB/CIFS implementation.
+   Samba Active Directory authentication policy functions
+
+   Copyright (C) Catalyst.Net Ltd 2023
+
+   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 "lib/replace/replace.h"
+#include "source4/kdc/authn_policy.h"
+#include "source4/kdc/authn_policy_impl.h"
+
+bool authn_policy_is_enforced(const struct authn_policy *policy)
+{
+	return policy->enforced;
+}
+
+/* Authentication policies for Kerberos clients. */
+
+/* Get the TGT lifetime enforced by an authentication policy. */
+int64_t authn_policy_enforced_tgt_lifetime(const struct authn_kerberos_client_policy *policy)
+{
+	if (policy == NULL) {
+		return 0;
+	}
+
+	if (!authn_policy_is_enforced(&policy->policy)) {
+		return 0;
+	}
+
+	return policy->tgt_lifetime;
+}
+
+/* Authentication policies for NTLM clients. */
+
+/* Return whether an authentication policy enforces device restrictions. */
+static bool authn_policy_ntlm_device_restrictions_present(const struct authn_ntlm_client_policy *policy)
+{
+	if (policy == NULL) {
+		return false;
+	}
+
+	return policy->allowed_to_authenticate_from.data != NULL;
+}
+
+/* Check whether the client is allowed to authenticate using NTLM. */
+NTSTATUS authn_policy_ntlm_apply_device_restriction(const char *client_account_name,
+						    const char *device_account_name,
+						    const struct authn_ntlm_client_policy *client_policy)
+{
+	/*
+	 * If NTLM authentication is disallowed and the policy enforces a device
+	 * restriction, deny the authentication.
+	 */
+
+	if (!authn_policy_ntlm_device_restrictions_present(client_policy)) {
+		return NT_STATUS_OK;
+	}
+
+	/*
+	 * Although MS-APDS doesn’t state it, AllowedNTLMNetworkAuthentication
+	 * applies to interactive logons too.
+	 */
+	if (client_policy->allowed_ntlm_network_auth) {
+		return NT_STATUS_OK;
+	}
+
+	if (authn_policy_is_enforced(&client_policy->policy)) {
+		return NT_STATUS_ACCOUNT_RESTRICTION;
+	} else {
+		return NT_STATUS_OK;
+	}
+}