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Rushing Attacks and Defense in Wireless Ad Hoc Network Routing Protocols

Yih-Chun Hu, Adrian Perrig, and David B. Johnson

Presented By: Nitin Subramanian(Slides Courtesy: Sandeep Mapakshi

CS 6910-ACIS – Project 6Instructor: Prof. Leszek T. Lilien, Fall 2006

Department of Computer ScienceWestern Michigan University)

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Outline

On-Demand Routing Protocols Rushing Attacks Rushing Attack Prevention Evaluation Conclusion

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On-Demand Route Discovery

A

A

A-B

A-C

A-C-E

A-C-E

A-C-E

A-B-D

A-B-D-GA-B-D-G

A-B-D-G

B

G

D

E

C

A

F

H

source

Destination

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The Rushing Attack On-demand routing protocols use duplicate suppression at each node: first

ROUTE REQUEST that reaches a node is considered legitimate, next are discarded (all have the same identifier, higher identifiers denote new requests)

Attacker scatters RREQ quickly throughout the network suppressing any later legitimate RREQ

Initiator will be unable to discover any usable routes containing at least two hops

An effective denial-of-service attack

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Why is the Attack Possible?

An attacker can send faster, by avoiding the delays that are part of the design of both routing and MAC (802.11b) protocols.

Why Delay in ROUTE REQUEST forwarding ? In a MAC protocols using time division On-demand protocols generally specify a delay Remove these delays at both the MAC and routing layers?

- more collisions

Attacker can send at a higher wireless transmission level

An attacker can take advantage of a wormhole, to create flood rushing attacks, use the wormhole to rush the packets ahead of the normal flow

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Rushing Attack

S

D

Slide courtesy: [2]

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Rushing Attack Example

●A sends a ROUTE REQUEST

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Rushing Attack Example

●A sends a ROUTE REQUEST

●B forwards the REQUEST without checking the signature, or otherwise rushes the REQUEST

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Rushing Attack Example

●A sends a ROUTE REQUEST

●B forwards the REQUEST without checking the signature, or otherwise rushes the REQUEST

●C correctly processes the REQUEST, and forwards it later as a result

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Rushing Attack Example

●A sends a ROUTE REQUEST

●B forwards the REQUEST without checking the signature, or otherwiserushes the REQUEST

●C correctly processes the REQUEST, and forwards it later as a result

●Since D has already heard a REQUEST from this discovery, D discards the REQUEST

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Rushing Attack Example

●B rushes the REQUEST

●C forwards it later

●Since D has already heard a REQUEST from this discovery, D discards the REQUEST

●A discovers a path through B because B rushed the REQUEST

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Rushing Attack Example

Route discovery process under no attack

B

E

D

C

ARoute Query

Route Query

Route Query

Route Reply

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Rushing Attack ExampleRoute discovery process under attack

B

E

D

C

ARoute Query

Route Query

Route Query

Route Reply

Attacker Attacker

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Wormhole Attack Attacker records a packet at one location in the network,

tunnels the packet to another location. Packets may be replayed from the far end of the wormhole. Puts attacker in a powerful position. It’s a replay so authentication does not help

Applications of the Wormhole Attack Denial-of-Service Routing Disruptions Unauthorized Access

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Routing Tree

Adapted from Chris Karlof and David Wagner's WSNPA slides

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Routing

Adapted from Chris Karlof and David Wagner's WSNPA slides

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Wormhole Attack Tunnel packets received in

one place of the network and replay them in another place

The attacker can have no key material. All it requires is two transceivers and one high quality out-of-band channel

Adapted from Chris Karlof and David Wagner's WSNPA slides

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Disrupted Routing Most packets will be routed

to the wormhole

The wormhole can drop packets or selectively forward packets to avoid detection

Adapted from Chris Karlof and David Wagner's WSNPA slides

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What Protocols Are Vulnerable?

On-demand unsecure (AODV, DSR) and secure (ARAN, Ariadne, etc) protocols

Result: when under attack, the routing protocol will not be able to discover paths longer than 2 hops

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Network Assumption Network links are bidirectional

Ignore unidirectional links

Ignore jamming attack Requires additional hardware Easier to detect

Disregard attacks on MAC protocol MAC (Medium Access Control) ALOHA and Slotted ALOHA

Medium-sized 50 ～ 500 nodes Clustering

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Security Assumptions And Key Setup

Fast authentication protocol Instantly-verifiable broadcast authentication

Keys setup Broadcast authentication key are distributed in

advance

Powerful attacker Coordinated attacker

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Secure Routing Requirements And Protocol

Secure Neighbor Detection Secure route delegation Randomized ROUTE REQUEST forwarding

Single-Hop?

Gather nREQUESTS;

RandomlyChoose 1

Secure NeighborDetection

Original RoutingProtocol

yes

no

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Secure Neighbor Detection Neighbor Detection

Two nodes detect a bidirectional link between themselves In Proactive routing protocol In Reactive routing protocol

Requirements Sender-receiver can check that the other is within the normal

communication range Node needs to hear Neighbor Request

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Secure Neighbor Detection Three-round mutual authentication protocol

S broadcasts a Neighbor Request packet R return a Neighbor Reply packet to S S sends a Neighbor Verification to B

Short delay timing Within a maximum communication range

neighbor Request broadcast neighbor reply

sender receiver

neighbor verfication

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Notation

M

M

R

MA

MA

MBA

AHMBA

A

A

BA

signature its with message broadcasts node that means

,:

nonce the withedconcatenat idnetifier s A'of hash the

and message the sends node that means

,:

nonce long bit an selectsrandmoly node that denotes

1,0:

nodes ingcommunicat denote or

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Secure Neighbor Detection (cont.)

3

3

2

2

1

1

,:

,,,,ion VerificatNeighbor:

,:

,,,,Reply Neighbor

1,0:

,:

,,onSolicitati Neighbor

1,0:

3

3

213

2

2

212

2

1

1

11

1

M

M

M

M

R

M

M

R

MRS

MHSign

RSMS

MSR

MHSign

RSM

R

MS

MHSign

SM

S

Nonces η1, η2

freshness

S

R1

R2

<M1,ΣM1>

<M2,ΣM2><M3,ΣM3>

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Secure Neighbor Detection (cont.)

Integration with an On-Demand Protocol A ＊ : REQUEST || Neighbor RequestA

BA: Neighbor ReplyBA || Neighbor RequestB

AB: Neighbor VerificationAB || Neighbor ReplyAB

B ＊ : REQUEST || Neighbor VerificationAB

|| Neighbor VerificationBA

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Secure Route Delegation

Delegate neighbor to forward the Route Request packet To verify that both nodes of each adjacent node pair indeed

believes to be a neighbor

A received ROUTE REQUESTSR || id MA =<Route Delegation,A,B,S,R,id>

ΣMA =Sign(H(MA))AB: <ΣMA>

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Randomized Message Forwarding To minimize the chance that a rushing adversary can dominate all returned

routes

Randomized message forwarding Collects a number of REQUESTs Selects a REQUEST at random to forward

The number of REQUEST packets collected The more the better?

The algorithm by which timeouts are chosen Topology closer Geographically closer Randomly

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Secure Route Discovery To secure any protocol using an on-demand Route Discovery protocol

Secure Neighbor Detection Secure route delegation Randomized ROUTE REQUEST forwarding

To limit the number of REQUESTs that traverse an attacker

The nodes that don’t have n distinct path to the source of the REQUEST Choose a random timeout

Two addition security optimizations Each REQUEST signed Use location information

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Evaluation

Simulation Evaluation Underlying protocol: Adriane HORS as broadcast signature 100 nodes 1000 m x 1000 m Random waypoint model Pause Time: 0, 30, 60, 120, 300, 600, 900 Workload: 5 flows

4 packets per second 64-byte packets

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Overall Evaluation

RAP adds significant costs Higher costs due to congestion at lower bit rates. RAP is designed to be used only when necessary

Only when underlying protocol is unable to discover a working route

Security Analysis Attacker needs to propagate ROUTE REQUEST from each

ROUTE DISCOVERY from many locations. Wouldn’t do it if they considered due to intrusion detection

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Conclusion

Described the Rushing attack

Presented RAP (Rushing Attack Prevention)

RAP incurs higher overhead, but it can find usable routes when other protocols cannot work

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[Backup Slides] Packet Delivery Ratio

% of Offered traffic DSR

99.8% to 100% Ariadne

95% to 100% RAP

7.6% to 47.7% MAC-layer congestion

Slide courtesy: [2]

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[Backup Slides] Median Latency

DSR and Ariadne zero mean latency

RAP Congestion Waiting to forward a

REQUEST

Slide courtesy: [2]

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[Backup Slides] Packet Overhead

5 flows has 5x as much overhead

Reduces usefulness Overhead should reduce

when congestion not an issue

Slide courtesy: [2]

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[Backup Slides] Introduction

Wireless Ad hoc network a collection of mobile computers (or nodes) cooperate

to forward packets dynamic topology self-organization

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[Backup Slides] Introduction (cont.)

Routing protocol Transport Subsystem Neighbor State Maintenance Database Maintenance

Ad hoc network routing protocols Run in untrusted environments Provide resilience against misconfigured nodes

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[Backup Slides] Routing Protocols

Proactive routing protocol Table-Driven routing protocol

Reactive routing protocol Source-Initiated On-Demand routing protocol Forward ROUTE REQUEST packets when needed

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[Backup Slides] Comparison between Table-Driven Routing and On-Demand Routing

Table-driven Routing On-demand Routing

Availability of Routing information

Immediately from Route Table

After Route discovery

Route updatesPeriodic advertisements When requested

Routing overhead Proportional to size of network regardless of network traffic

Proportional to number of communication nodes and increase with increased node mobility

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References

[1] Yih-Chun Hu,Adrian Perrig, David B.Johnson ,

“Rushing attacks and defense in wireless ad hoc network routing protocols”, Proceedings of the 2003 ACM workshop on Wireless security, San Diego, CA, USA. Available at: http://www.ece.cmu.edu/~adrian/projects/secure-routing/wise2003.pdf

[2] Rushing Attacks and Defense in Wireless Ad Hoc Network Routing Protocols Yih-Chun Hu, Adrian Perrig, and David B. Johnson

Presenter: Tammy Nguyen. Available at: http://www.eecs.wsu.edu/~smedidi/teaching/Spring05/rushing1.ppt