Return-Path: From: Grzegorz Kolodziejczyk To: linux-bluetooth@vger.kernel.org Subject: [PATCH BlueZ] client: Fix reading long values Date: Wed, 7 Mar 2018 17:09:18 +0100 Message-Id: <20180307160918.12156-1-grzegorz.kolodziejczyk@codecoup.pl> Sender: linux-bluetooth-owner@vger.kernel.org List-ID: While value has more than single MTU can carry long read procedure will be triggered. In such cases offset need to bo considered while getting value from storage. --- client/gatt.c | 41 ++++++++++++++++++++++++++++++++++++++++- 1 file changed, 40 insertions(+), 1 deletion(-) diff --git a/client/gatt.c b/client/gatt.c index 8c818d8c1..9d8c50d47 100644 --- a/client/gatt.c +++ b/client/gatt.c @@ -1412,6 +1412,39 @@ static const GDBusPropertyTable chrc_properties[] = { { } }; +static int parse_offset(DBusMessageIter *iter, uint16_t *offset) +{ + DBusMessageIter dict; + + if (dbus_message_iter_get_arg_type(iter) != DBUS_TYPE_ARRAY) + return -EINVAL; + + dbus_message_iter_recurse(iter, &dict); + + while (dbus_message_iter_get_arg_type(&dict) == DBUS_TYPE_DICT_ENTRY) { + const char *key; + DBusMessageIter value, entry; + int var; + + dbus_message_iter_recurse(&dict, &entry); + dbus_message_iter_get_basic(&entry, &key); + + dbus_message_iter_next(&entry); + dbus_message_iter_recurse(&entry, &value); + + var = dbus_message_iter_get_arg_type(&value); + if (strcasecmp(key, "offset") == 0) { + if (var != DBUS_TYPE_UINT16) + return -EINVAL; + dbus_message_iter_get_basic(&value, offset); + } + + dbus_message_iter_next(&dict); + } + + return 0; +} + static DBusMessage *read_value(DBusMessage *msg, uint8_t *value, uint16_t value_len) { @@ -1433,8 +1466,14 @@ static DBusMessage *chrc_read_value(DBusConnection *conn, DBusMessage *msg, void *user_data) { struct chrc *chrc = user_data; + DBusMessageIter iter; + uint16_t offset = 0; + + dbus_message_iter_init(msg, &iter); + + parse_offset(&iter, &offset); - return read_value(msg, chrc->value, chrc->value_len); + return read_value(msg, &chrc->value[offset], chrc->value_len - offset); } static int parse_value_arg(DBusMessageIter *iter, uint8_t **value, int *len) -- 2.13.6