From 2541790f21a2db74ea556182210d5f4c608640e6 Mon Sep 17 00:00:00 2001
From: Daniel Jobson <jobson@tillitis.se>
Date: Thu, 12 Sep 2024 13:19:40 +0200
Subject: [PATCH] WIP management app

---
 hw/application_fpga/Makefile          |  9 ++--
 hw/application_fpga/fw/tk1/mgmt_app.c | 75 +++++++++++++++++++++++++++
 hw/application_fpga/fw/tk1/mgmt_app.h | 15 ++++++
 3 files changed, 96 insertions(+), 3 deletions(-)
 create mode 100644 hw/application_fpga/fw/tk1/mgmt_app.c
 create mode 100644 hw/application_fpga/fw/tk1/mgmt_app.h

diff --git a/hw/application_fpga/Makefile b/hw/application_fpga/Makefile
index ff375b9..337ad02 100644
--- a/hw/application_fpga/Makefile
+++ b/hw/application_fpga/Makefile
@@ -117,7 +117,8 @@ FIRMWARE_DEPS = \
 	$(P)/fw/tk1/preload_app.h \
 	$(P)/fw/tk1/auth_app.h \
 	$(P)/fw/tk1/htif.h \
-	$(P)/fw/tk1/rng.h
+	$(P)/fw/tk1/rng.h \
+	$(P)/fw/tk1/mgmt_app.h
 
 FIRMWARE_OBJS = \
 	$(P)/fw/tk1/main.o \
@@ -133,7 +134,8 @@ FIRMWARE_OBJS = \
 	$(P)/fw/tk1/preload_app.o \
 	$(P)/fw/tk1/auth_app.o \
 	$(P)/fw/tk1/htif.o \
-	$(P)/fw/tk1/rng.o
+	$(P)/fw/tk1/rng.o \
+	$(P)/fw/tk1/mgmt_app.o
 
 FIRMWARE_SOURCES = \
 	$(P)/fw/tk1/main.c \
@@ -148,7 +150,8 @@ FIRMWARE_SOURCES = \
 	$(P)/fw/tk1/preload_app.c \
 	$(P)/fw/tk1/auth_app.c \
 	$(P)/fw/tk1/htif.c \
-	$(P)/fw/tk1/rng.c
+	$(P)/fw/tk1/rng.c \
+	$(P)/fw/tk1/mgmt_app.c
 
 TESTFW_OBJS = \
 	$(P)/fw/testfw/main.o \
diff --git a/hw/application_fpga/fw/tk1/mgmt_app.c b/hw/application_fpga/fw/tk1/mgmt_app.c
new file mode 100644
index 0000000..6d56e53
--- /dev/null
+++ b/hw/application_fpga/fw/tk1/mgmt_app.c
@@ -0,0 +1,75 @@
+// Copyright (C) 2024 - Tillitis AB
+// SPDX-License-Identifier: GPL-2.0-only
+
+#include "mgmt_app.h"
+#include "auth_app.h"
+#include "lib.h"
+#include "partition_table.h"
+
+#include <stdbool.h>
+
+/* Returns true if an management app is already registered */
+static bool mgmt_app_registered(management_app_metadata_t *mgmt_table)
+{
+
+	if (mgmt_table->status == 0x00) {
+		/* No management app registered */
+		return false;
+		// TODO: Should we also check nonce, authentication digest for
+		// non-zero?
+	}
+
+	return true;
+}
+
+/* Authenticate an management app */
+bool mgmt_app_authenticate(management_app_metadata_t *mgmt_table)
+{
+	if (!mgmt_app_registered(mgmt_table)) {
+		return false;
+	}
+
+	return auth_app_authenticate(&mgmt_table->auth);
+}
+
+/* Register an management app, returns zero on success */
+int mgmt_app_register(partition_table_t *part_table)
+{
+	/* Check if the current app is the mgmt app */
+	if (mgmt_app_authenticate(&part_table->mgmt_app_data)) {
+		return 0;
+	}
+
+	/* Check if another management app is registered */
+	if (mgmt_app_registered(&part_table->mgmt_app_data)) {
+		return -1;
+	}
+
+	auth_app_create(&part_table->mgmt_app_data.auth);
+	part_table->mgmt_app_data.status = 0x01;
+
+	part_table_write(part_table);
+
+	return 0;
+}
+
+/* Unregister the currently registered app, returns zero on success */
+int mgmt_app_unregister(partition_table_t *part_table)
+{
+	/* Only the management app should be able to unregister itself */
+	if (!mgmt_app_authenticate(&part_table->mgmt_app_data)) {
+		return -1;
+	}
+
+	part_table->mgmt_app_data.status = 0;
+
+	memset(part_table->mgmt_app_data.auth.nonce, 0x00,
+	       sizeof(part_table->mgmt_app_data.auth.nonce));
+
+	memset(part_table->mgmt_app_data.auth.authentication_digest, 0x00,
+	       sizeof(part_table->mgmt_app_data.auth.authentication_digest));
+
+	part_table_write(part_table);
+
+	return 0;
+}
diff --git a/hw/application_fpga/fw/tk1/mgmt_app.h b/hw/application_fpga/fw/tk1/mgmt_app.h
new file mode 100644
index 0000000..611f3f6
--- /dev/null
+++ b/hw/application_fpga/fw/tk1/mgmt_app.h
@@ -0,0 +1,15 @@
+// Copyright (C) 2024 - Tillitis AB
+// SPDX-License-Identifier: GPL-2.0-only
+
+#ifndef MGMT_APP_H
+#define MGMT_APP_H
+
+#include "partition_table.h"
+
+#include <stdbool.h>
+
+bool mgmt_app_authenticate(management_app_metadata_t *mgmt_table);
+int mgmt_app_register(partition_table_t *part_table);
+int mgmt_app_unregister(partition_table_t *part_table);
+
+#endif