From bc6b65c7943aa7068dc3d7d0f8511a2c71eefb1d Mon Sep 17 00:00:00 2001
From: Matthias Ringwald <matthias@ringwald.ch>
Date: Thu, 9 Jan 2020 17:11:58 +0100
Subject: [PATCH] att_db_util: track number of bytes to include in database
 hash

---
 src/ble/att_db_util.c          | 41 ++++++++++++++++++++++++++++++
 src/ble/att_db_util.h          |  5 ++++
 test/att_db/att_db_util_test.c | 46 +++++++++++++++++++++++++++++++++-
 3 files changed, 91 insertions(+), 1 deletion(-)

diff --git a/src/ble/att_db_util.c b/src/ble/att_db_util.c
index de715cbd2..38ba2d9d0 100644
--- a/src/ble/att_db_util.c
+++ b/src/ble/att_db_util.c
@@ -60,6 +60,7 @@ static uint8_t * att_db;
 static uint16_t  att_db_size;
 static uint16_t  att_db_max_size;
 static uint16_t  att_db_next_handle;
+static uint16_t  att_db_hash_len;
 
 static void att_db_util_set_end_tag(void){
 	// end tag
@@ -79,9 +80,43 @@ void att_db_util_init(void){
 	att_db[0] = ATT_DB_VERSION;
 	att_db_size = 1;
 	att_db_next_handle = 1;
+	att_db_hash_len = 0;
 	att_db_util_set_end_tag();
 }
 
+static bool att_db_util_hash_include_with_value(uint16_t uuid16){
+    /* «Primary Service», «Secondary Service», «Included Service», «Characteristic», or «Characteristic Extended Properties» */
+    switch (uuid16){
+        case GATT_PRIMARY_SERVICE_UUID:
+        case GATT_SECONDARY_SERVICE_UUID:
+        case GATT_INCLUDE_SERVICE_UUID:
+        case GATT_CHARACTERISTICS_UUID:
+        case GATT_CHARACTERISTIC_EXTENDED_PROPERTIES:
+            return true;
+        default:
+            return false;
+    }
+}
+
+static bool att_db_util_hash_include_without_value(uint16_t uuid16){
+    /*  «Characteristic User Description», «Client Characteristic Configuration», «Server Characteristic Configuration»,
+     * «Characteristic Aggregate Format», «Characteristic Format» */
+    switch (uuid16){
+        case GATT_CHARACTERISTIC_USER_DESCRIPTION:
+        case GATT_CLIENT_CHARACTERISTICS_CONFIGURATION:
+        case GATT_SERVER_CHARACTERISTICS_CONFIGURATION:
+        case GATT_CHARACTERISTIC_PRESENTATION_FORMAT:
+        case GATT_CHARACTERISTIC_AGGREGATE_FORMAT:
+            return true;
+        default:
+            return false;
+    }
+}
+
+uint16_t att_db_util_hash_len(void){
+    return att_db_hash_len;
+}
+
 /**
  * asserts that the requested amount of bytes can be stored in the att_db
  * @returns TRUE if space is available
@@ -125,6 +160,12 @@ static void att_db_util_add_attribute_uuid16(uint16_t uuid16, uint16_t flags, ui
 	(void)memcpy(&att_db[att_db_size], data, data_len);
 	att_db_size += data_len;
 	att_db_util_set_end_tag();
+
+	if (att_db_util_hash_include_with_value(uuid16)){
+	    att_db_hash_len += 4 + data_len;
+	} else if (att_db_util_hash_include_without_value(uuid16)){
+        att_db_hash_len += 4;
+	}
 }
 
 static void att_db_util_add_attribute_uuid128(const uint8_t * uuid128, uint16_t flags, uint8_t * data, uint16_t data_len){
diff --git a/src/ble/att_db_util.h b/src/ble/att_db_util.h
index 89afaa9d4..03117a2f0 100644
--- a/src/ble/att_db_util.h
+++ b/src/ble/att_db_util.h
@@ -161,6 +161,11 @@ uint8_t * att_db_util_get_address(void);
  */
 uint16_t att_db_util_get_size(void);
 
+/**
+ * @brief Get number of bytes that are included in GATT Database Hash
+ */
+uint16_t att_db_util_hash_len(void);
+
 /* API_END */
 
 #if defined __cplusplus
diff --git a/test/att_db/att_db_util_test.c b/test/att_db/att_db_util_test.c
index fd8f99a16..090aa4c27 100644
--- a/test/att_db/att_db_util_test.c
+++ b/test/att_db/att_db_util_test.c
@@ -62,6 +62,17 @@ uint8_t counter_service_uuid[] = { 0x00, 0x00, 0xFF, 0x10, 0x00, 0x00, 0x10, 0x0
 // 0000FF11-0000-1000-8000-00805F9B34FB
 uint8_t counter_characteristic_uuid[] = { 0x00, 0x00, 0xFF, 0x11, 0x00, 0x00, 0x10, 0x00, 0x80, 0x00, 0x00, 0x80, 0x5F, 0x9B, 0x34, 0xFB};
 
+// gatt database hash test message
+static const uint8_t gatt_database_hash_test_message[] = {
+        0x01, 0x00, 0x00, 0x28, 0x00, 0x18, 0x02, 0x00, 0x03, 0x28, 0x0A, 0x03, 0x00, 0x00, 0x2A, 0x04,
+        0x00, 0x03, 0x28, 0x02, 0x05, 0x00, 0x01, 0x2A, 0x06, 0x00, 0x00, 0x28, 0x01, 0x18, 0x07, 0x00,
+        0x03, 0x28, 0x20, 0x08, 0x00, 0x05, 0x2A, 0x09, 0x00, 0x02, 0x29, 0x0A, 0x00, 0x03, 0x28, 0x0A,
+        0x0B, 0x00, 0x29, 0x2B, 0x0C, 0x00, 0x03, 0x28, 0x02, 0x0D, 0x00, 0x2A, 0x2B, 0x0E, 0x00, 0x00,
+        0x28, 0x08, 0x18, 0x0F, 0x00, 0x02, 0x28, 0x14, 0x00, 0x16, 0x00, 0x0F, 0x18, 0x10, 0x00, 0x03,
+        0x28, 0xA2, 0x11, 0x00, 0x18, 0x2A, 0x12, 0x00, 0x02, 0x29, 0x13, 0x00, 0x00, 0x29, 0x00, 0x00,
+        0x14, 0x00, 0x01, 0x28, 0x0F, 0x18, 0x15, 0x00, 0x03, 0x28, 0x02, 0x16, 0x00, 0x19, 0x2A
+};
+
 void CHECK_EQUAL_ARRAY(const uint8_t * expected, uint8_t * actual, int size){
     for (int i=0; i<size; i++){
         printf("%03u: %02x - %02x\n", i, expected[i], actual[i]);
@@ -86,7 +97,7 @@ TEST(AttDbUtil, LeCounterDb){
     att_db_util_add_characteristic_uuid16(GAP_DEVICE_NAME_UUID, ATT_PROPERTY_READ, ATT_SECURITY_NONE, ATT_SECURITY_NONE, (uint8_t*)"SPP+LE Counter", 14);
 
     att_db_util_add_service_uuid16(0x1801);
-    att_db_util_add_characteristic_uuid16(0x2a05, ATT_PROPERTY_READ, ATT_SECURITY_NONE, ATT_SECURITY_NONE, NULL, 0);
+    att_db_util_add_characteristic_uuid16(GAP_SERVICE_CHANGED, ATT_PROPERTY_READ, ATT_SECURITY_NONE, ATT_SECURITY_NONE, NULL, 0);
 
     att_db_util_add_service_uuid128(counter_service_uuid);
     att_db_util_add_characteristic_uuid128(counter_characteristic_uuid, ATT_PROPERTY_READ | ATT_PROPERTY_NOTIFY | ATT_PROPERTY_DYNAMIC, ATT_SECURITY_NONE, ATT_SECURITY_NONE, NULL, 0);
@@ -94,12 +105,45 @@ TEST(AttDbUtil, LeCounterDb){
     uint8_t * addr = att_db_util_get_address();
     uint16_t  size = att_db_util_get_size();
 
+    printf("LE Counter DB\n");
     printf_hexdump(addr, size);
 
     CHECK_EQUAL(size, (uint16_t)sizeof(profile_data));
     CHECK_EQUAL_ARRAY(profile_data, addr, size);
 }
 
+TEST(AttDbUtil, GattHash){
+    const uint8_t appearance[] = {0};
+    const uint8_t service_changed[] = {0} ;
+    const uint8_t supported_features[] = {0} ;
+    const uint8_t extended_properties[] = {0,0} ;
+    const uint8_t battery_level[] = { 100 } ;
+    att_db_util_add_service_uuid16(GAP_SERVICE_UUID);
+    att_db_util_add_characteristic_uuid16(GAP_DEVICE_NAME_UUID, ATT_PROPERTY_READ, ATT_SECURITY_NONE, ATT_SECURITY_NONE, (uint8_t*)"HASH", 4);
+    att_db_util_add_characteristic_uuid16(GAP_APPEARANCE_UUID, ATT_PROPERTY_READ, ATT_SECURITY_NONE, ATT_SECURITY_NONE, (uint8_t*)appearance, sizeof(appearance));
+    att_db_util_add_service_uuid16(0x1801);
+    att_db_util_add_characteristic_uuid16(GAP_SERVICE_CHANGED, ATT_PROPERTY_READ | ATT_PROPERTY_INDICATE, ATT_SECURITY_NONE, ATT_SECURITY_NONE, (uint8_t*)service_changed, sizeof(service_changed));
+    att_db_util_add_characteristic_uuid16(0x2b29, ATT_PROPERTY_READ | ATT_PROPERTY_WRITE, ATT_SECURITY_NONE, ATT_SECURITY_NONE, (uint8_t*)supported_features, sizeof(supported_features));
+    att_db_util_add_characteristic_uuid16(0x2b2a, ATT_PROPERTY_READ | ATT_PROPERTY_DYNAMIC, ATT_SECURITY_NONE, ATT_SECURITY_NONE, NULL, 0);
+    att_db_util_add_service_uuid16(0x1808);
+    att_db_util_add_included_service_uuid16(0x0014, 0x0016, 0x180f);
+    att_db_util_add_characteristic_uuid16(0x2a18, ATT_PROPERTY_READ | ATT_PROPERTY_EXTENDED_PROPERTIES | ATT_PROPERTY_INDICATE, ATT_SECURITY_NONE, ATT_SECURITY_NONE, NULL, 0);
+    att_db_util_add_descriptor_uuid16(0x2900, 0, ATT_SECURITY_NONE, ATT_SECURITY_NONE, (uint8_t*)extended_properties, sizeof(extended_properties));
+    att_db_util_add_secondary_service_uuid16(0x180f);
+    att_db_util_add_characteristic_uuid16(0x2a18, ATT_PROPERTY_READ, ATT_SECURITY_NONE, ATT_SECURITY_NONE, (uint8_t*)battery_level, sizeof(battery_level));
+
+    uint8_t * addr = att_db_util_get_address();
+    uint16_t  size = att_db_util_get_size();
+
+    printf("HASH DB, len %u\n", size);
+    printf_hexdump(addr, size);
+
+    uint16_t hash_len = att_db_util_hash_len();
+    printf("Hashable part len %u\n", hash_len);
+
+CHECK_EQUAL(sizeof(gatt_database_hash_test_message), hash_len);
+}
+
 int main (int argc, const char * argv[]){
     return CommandLineTestRunner::RunAllTests(argc, argv);
 }