Devices in a sensor network need to work in a hostile environment and they are usually powered by batteries. Yet the whole purpose of deploying a sensor network is to perform distributed collaborative computing, possibly in a massive scale. In a hostile computing environment, the sensor devices might be routinely tampered with. Together with the possibility of faulty devices due to extreme conditions or low power, the trustworthiness of a device varies. Specifically, a device should only communicate with another device which has a trust level above a certain threshold. However, setting up trusted communication channels among sensor devices remains a major challenge. In this paper, we propose a trust-based routing scheme in sensor networks for providing a high level of robustness in node selection based on packet trust requirement with lifetime consideration. Our protocol allows messages to be routed through malicious and faulty devices with the selection of trusted neighbors. On the other hand, the network lifetime can also be prolonged by selecting those with their sensing functions covered by some existing nodes. Simulation results show that our scheme is possible to prolong the lifetime of sensor networks and maintain certain satisfactory delivery ratio.