Prabal Dutta and Jonathan W. Hui and David Chiyuan Chu and David E. Culler

EECS Department, University of California, Berkeley

Technical Report No. UCB/EECS-2005-7

October 14, 2005

http://www2.eecs.berkeley.edu/Pubs/TechRpts/2005/EECS-2005-7.pdf

A number of multi-hop wireless reprogramming systems have emerged for sensor network retasking but none of these systems support a cryptographically-strong, public-key-based system for program authentication or any form of recovery from authenticated, but Byzantine, programs. The traditional techniques for authenticating a program and recovering from Byzantine user programs, namely a digital signature of the program hash and hardware-based memory protection, respectively, are not suited to resource-contrained sensor nodes. We present techniques that are consistent with the limited resources of sensor networks, can be used to secure existing wireless reprogramming systems, and allow recovery from Byzantine programs. Our solution to the secure reprogramming problem is based on authenticated streams. A program image consists of several code and data segments that are mapped to a series of messages for transmission over the network. A hash of the first message in this series is digitally signed and the hash and signature are prepended to the series. The signed hash authenticates the first message, which in turn contains a hash of the second message. Similarly, the second message contains a hash of the third message, and so on, recursively binding each message to the one logically preceding it in the series through the hash chain. The solution to the recovery problem requires both on- and off-chip hardware support in the form of a write-protected boot block and a grenade timer. Recovery is enforced by periodically resetting the node which executes a trusted bootloader located in the boot block. We implemented the security and recovery primitives using TinyOS and demonstrated that the overhead incurred is small compared with the cost of network programming.

---

BibTeX citation:

@techreport{Dutta:EECS-2005-7,
    Author= {Dutta, Prabal and Hui, Jonathan W. and Chu, David Chiyuan and Culler, David E.},
    Title= {Towards Secure Network Programming and Recovery in Wireless Sensor Networks},
    Year= {2005},
    Month= {Oct},
    Url= {http://www2.eecs.berkeley.edu/Pubs/TechRpts/2005/EECS-2005-7.html},
    Number= {UCB/EECS-2005-7},
    Abstract= {A number of multi-hop wireless reprogramming systems have emerged for
sensor network retasking but none of these systems support a
cryptographically-strong, public-key-based system for program
authentication or any form of recovery from authenticated, but
Byzantine, programs.  The traditional techniques for authenticating a
program and recovering from Byzantine user programs, namely a digital
signature of the program hash and hardware-based memory protection,
respectively, are not suited to resource-contrained sensor nodes.  We
present techniques that are consistent with the limited resources of
sensor networks, can be used to secure existing wireless reprogramming
systems, and allow recovery from Byzantine programs.  Our solution to
the secure reprogramming problem is based on authenticated streams.  A
program image consists of several code and data segments that are
mapped to a series of messages for transmission over the network.  A
hash of the first message in this series is digitally signed and the
hash and signature are prepended to the series.  The signed hash
authenticates the first message, which in turn contains a hash of the
second message.  Similarly, the second message contains a hash of the
third message, and so on, recursively binding each message to the one
logically preceding it in the series through the hash chain.  The
solution to the recovery problem requires both on- and off-chip
hardware support in the form of a write-protected boot block and a
grenade timer.  Recovery is enforced by periodically resetting the
node which executes a trusted bootloader located in the boot block.
We implemented the security and recovery primitives using TinyOS and
demonstrated that the overhead incurred is small compared with the
cost of network programming.},
}

EndNote citation:

%0 Report
%A Dutta, Prabal 
%A Hui, Jonathan W. 
%A Chu, David Chiyuan 
%A Culler, David E. 
%T Towards Secure Network Programming and Recovery in Wireless Sensor Networks
%I EECS Department, University of California, Berkeley
%D 2005
%8 October 14
%@ UCB/EECS-2005-7
%U http://www2.eecs.berkeley.edu/Pubs/TechRpts/2005/EECS-2005-7.html
%F Dutta:EECS-2005-7