Post on 25-Apr-2020
Securing Wireless Ad Hoc Networks
Valérie Gayraud & Bruno Tharon
ISS Master 12th March 2003
MP 71 project
Securing Wireless Ad Hoc Networks PRESENTATION - 1Valérie Gayraud & Bruno Tharon
Agenda– Goal of the project– What is a wireless ad hoc network?• Introduction
• Security Issues Analysis
– Risk analysis– Results
• Proposed Solutions
– Models from literature– Securing routing– A specific solution: Ariadne
• Conclusion – Project follow-up– Personal comments
Securing Wireless Ad Hoc Networks PRESENTATION - 2Valérie Gayraud & Bruno Tharon
Goal of the project
• List existing security issues in Wireless Ad Hoc Networks (Risk Analysis Approach)
• List solutions and countermeasures
• Have a deeper look onto Routing issues & highlight solutions (MANET*)
• Explore a specific Routing solution (Ariadne)
(*)Mobile Ad Hoc NETworks
Securing Wireless Ad Hoc Networks PRESENTATION - 3Valérie Gayraud & Bruno Tharon
What is a Wireless Ad Hoc Network ?
Internet
Infrastructure mode
Wireless Ad Hocmode
Wire
Radio wave
Securing Wireless Ad Hoc Networks PRESENTATION - 4Valérie Gayraud & Bruno Tharon
• Collection of wireless mobile nodes*
• Capable of communicating with each other without the use of a network infrastructure
• The mobile hosts are not bound to any centralized control
• Each mobile station acts as a router
(*) Nodes can be: Laptop, PDA, domestic appliances …
What is a Wireless Ad Hoc Network ?
Securing Wireless Ad Hoc Networks PRESENTATION - 5Valérie Gayraud & Bruno Tharon
• Dynamic topology
• Bandwidth-constrained
• Variable capacity links
• Energy-constrained operation
• Limited physical security
What is a Wireless Ad Hoc Network ?(Features from RFC 2501)
• Autonomous Terminal
• Distributed Operation (cooperative mode)
• Lightweight Terminals
• Multi-hop Routing
• Self-configuration capability
Securing Wireless Ad Hoc Networks PRESENTATION - 6Valérie Gayraud & Bruno Tharon
Based on WLAN Technologies
Securing Wireless Ad Hoc Networks PRESENTATION - 7Valérie Gayraud & Bruno Tharon
• Personal Area Network (PAN) area
• Special event coverage
• Disaster recovery
What is a Wireless Ad Hoc Network ?(Possible Applications)
• Peer to peer network area
• Industrial area
• Cellular networks area
Civilian, Military, Medical areas
Securing Wireless Ad Hoc Networks PRESENTATION - 8Valérie Gayraud & Bruno Tharon
Agenda– Goal of the project– What is a wireless ad hoc network?• Introduction
• Security Issues Analysis
– Risk analysis– Results
• Proposed Solutions
– Models from literature– Securing routing– A specific solution: Ariadne
• Conclusion – Project follow-up– Personal comments
Securing Wireless Ad Hoc Networks PRESENTATION - 9Valérie Gayraud & Bruno Tharon
Security requirements(What kind of protection do we need ?in terms of confidentiality, availability, integrity, non-repudiation, anonymity)
Known threats(attacks scenarii)
Vulnerabilities(Is there any weaknesses in the
System ? technical/non technical specific)
Functions/data requiring protection(what do we need to be protected ?)
Risk assessmentTake into account all aspects to determine
the realistic threats that could exlpoitthe vulnerabilities to perform illegalaction onto sensitive functions/data.
Risk analysis
1
2
3
4
5
Risk Analysis (EBIOS Like)
Securing Wireless Ad Hoc Networks PRESENTATION - 10Valérie Gayraud & Bruno Tharon
Security requirements(What kind of protection do we need ?in terms of confidentiality, availability, integrity, non-repudiation, anonymity)
Known threats(attacks scenarii)
Vulnerabilities(Is there any weaknesses in the
System ? technical/non technical specific)
Functions/data requiring protection(what do we need to be protected ?)
Risk assessmentTake into account all aspects to determine
the realistic threats that could exlpoitthe vulnerabilities to perform illegalaction onto sensitive functions/data.
Risk analysis
1
2
3
4
5
Risk Analysis (EBIOS Like)
Securing Wireless Ad Hoc Networks PRESENTATION - 11Valérie Gayraud & Bruno Tharon
• Sensitive functions :- Routing - (Self)Configuration- Power management- Security functions
• Sensitive data : - Routing Protocol data- (Self)Configuration data- Power management data- Security Attributes
Risk AnalysisStep 1 : Assets requiring protection
Securing Wireless Ad Hoc Networks PRESENTATION - 12Valérie Gayraud & Bruno Tharon
• Authentication (corner stone)
• Confidentiality
• Availability
• Integrity
• Non-Repudiation
• Anonymity
Risk Analysis step 2 : Security Requirements
Securing Wireless Ad Hoc Networks PRESENTATION - 13Valérie Gayraud & Bruno Tharon
Risk Analysis step 3 : Typical Threats
Internal/externalattack
Passive attack(listen,collect) Active attack
(modification,replication,deletion)
Wired lineeavesdropping
Aireavesdropping
Informationdisclosure
Traffic analysis
ImpersonationUsurpation
Replay
Data modification
Denial of Service
Trojan Horses Viruses Worms Logical bombs
Securing Wireless Ad Hoc Networks PRESENTATION - 14Valérie Gayraud & Bruno Tharon
• Channels
• Nodes
• Absence of infrastructure
• Dynamically changing topology
• Routing mechanism
• Absence of centralized server
• Implemented OS in the Node
• WLAN’s vulnerabilities
Risk Analysis Step 4 : Vulnerabilities
Securing Wireless Ad Hoc Networks PRESENTATION - 15Valérie Gayraud & Bruno Tharon
Attacks on the basic mechanisms routing and configuration mechanism
Attacks on the security mechanisms
Results : Risks assessment
Securing Wireless Ad Hoc Networks PRESENTATION - 16Valérie Gayraud & Bruno Tharon
• Eavesdropping attacks
• Impersonation
• Physical attacks
• Information disclosure
Risks assessment : Potential Scenarios
• Denial of Service attacks• Routing table overflow• Radio jamming• Battery exhaustion• Software alteration attacks• Selfishness of the node
Securing Wireless Ad Hoc Networks PRESENTATION - 17Valérie Gayraud & Bruno Tharon
Agenda– Goal of the project– What is a wireless ad hoc network?• Introduction
• Security Issues Analysis
– Risk analysis– Results
• Conclusion – Project follow-up– Personal comments
• Proposed Solutions
– Models from literature– Securing routing– A specific solution: Ariadne
Securing Wireless Ad Hoc Networks PRESENTATION - 18Valérie Gayraud & Bruno Tharon
Solutions from Literature 1/2• Authentication
– Key agreement• Contributory• Distributory
– Duckling security policy model (Stajano / Anderson)• Imprinting: Temporary master/slave association ? Physical contact
– Self organized public key infrastructure• Certificates are created, stored and distributed by the users
• Confidentiality– Frequency hoping– Encryption
• Symmetric encryption preferred
• Anonymity– Pseudo-anonymity
Securing Wireless Ad Hoc Networks PRESENTATION - 19Valérie Gayraud & Bruno Tharon
Solutions from Literature 2/2• Devices integrity
– Tamper resistance– Tamper evidence
• Message integrity– Digital signature with public key
• Too computational– TESLA (A.Perrig, R. Canetti, D. Song, J.D.Tygar)
• Multicast operations• Authentication of the sender• Scalability to many possible receivers• Handle packets loss• Use a chain of key• Message authenticate with a key disclosed later• Precise synchronization of nodes required
Securing Wireless Ad Hoc Networks PRESENTATION - 20Valérie Gayraud & Bruno Tharon
TESLA• Kn random number generated by node A, Ki = h(Ki+1)
• “d”: disclosure time depends on– End to end network delay and loose synchronization
between nodes
Data Packet:Message MkMAC: MACKk ( Mk)Recent TESLA key: Kj
2Packet k from A to B
Data Packet:Message MjMAC: MACKi ( Mj )Recent TESLA key: Kk
1Packet j from A to B
kTime
j i
d d
Kj disclosed ? Reach B
Authentication of Packet j by B3
Securing Wireless Ad Hoc Networks PRESENTATION - 21Valérie Gayraud & Bruno Tharon
Broadcast
K is disclosed later in a subsequent message
SourceMessage authentication with secret key K
Destinations
TESLA
Securing Wireless Ad Hoc Networks PRESENTATION - 22Valérie Gayraud & Bruno Tharon
Taxonomy of Ad Hoc Routing ProtocolUnicast Rout ing
protocols
N o n Uniform Uni form
Neighbour se lect ion Cluster ingRout ing Area
Topo logy basedLink s tate protocol
Dest inat ion basedDistance Vector protoco l
React iveProact ive
A B R
T O R A
A O D V
F S R
W R P
D S D V
React iveProact ive
D S R
G S R
T B R P F
C E D A R
C B R P
Proact ive React ive
C G S R
H S R
Proact ive React ive
Z R P
O L S R
ZRP (Zone Rout ing Protocol ) D S D V (D y n a m i c destination -Sequenced Distance Vec tor Routing pro tocol)O S L R (Opt imized Link Sta teRout ing protocol) W R P (Wire less Routing Protocol)C E D A R ( Core -Extract ion Distr ibuted Ad Hoc Routing pro tocol) A O D V (Ad hoc On demand Distance Vec tor pro tocol )C B R P (Clus tered Based Rout ing protocol) T O R A (Tempora l ly-Ordered Rout ing Algor i thm protocol)GSR (Global State Routing pro tocol) A B R (Associated-B a s e d long l ived Routing Algor i thm protocol )D S R (Dynamic Source Rout ing protocol) T B R P F (Topology disseminat ion Based on Reverse Path Forwarding pro tocol)F S R (Fisheye State Rout ing pro tocol) C G S R (Clus terhead Ga teway Switch Rout ing protocol)HSR (Hierarchical State Rout ing protocol)
Securing Wireless Ad Hoc Networks PRESENTATION - 23Valérie Gayraud & Bruno Tharon
Taxonomy of Routing Protocols
• Route Discovery procedure: –Find a route to the destination
• Route Request• Route Reply
• Route Maintenance procedure:–Maintains connections
• Hello Messages• Route Error
Securing Wireless Ad Hoc Networks PRESENTATION - 24Valérie Gayraud & Bruno Tharon
Taxonomy of Routing Protocols
• Proactive Protocol:– Routing data continuously updated– Management data exchange between nodes to make
routes straight away available– Updating costs a lot and a change of topology impacts the
entire network
• Reactive Protocol:– No routing data held permanently– On demand route searching– unused routes are not handled but there’s a delay before
using a route and the searching route mechanism uses broadcast request
• Both (Hybrid Protocol) :
Securing Wireless Ad Hoc Networks PRESENTATION - 25Valérie Gayraud & Bruno Tharon
Taxonomy of Routing Protocols
• Uniform (same role for every node):–Distance Vector (destination based)–Link State (topology based)
• Non Uniform (some nodes handle routing):–Neighbor selection (election of nodes to handle
routing, similar as default gateway)–Clustering (Routing Areas), the network is divided
into several routing areas (same as GPRS/UMTS)
Securing Wireless Ad Hoc Networks PRESENTATION - 26Valérie Gayraud & Bruno Tharon
A Secure Routing ProtocolAriadne (Yih-Chun Hu, A. Perrig, D.B. Johnson, Mellon University)
• Secure on-demand routing protocol
• Prevents malicious injection or altering of routing data– Routing loop– Black hole– Detours
• Prevents denial of service attacks
• Authentication of routing messages– Shared secret keys– TESLA– Digital signature
Securing Wireless Ad Hoc Networks PRESENTATION - 27Valérie Gayraud & Bruno Tharon
Ariadne: ROUTE REQUEST
Route REQUEST Message:Initiator ATarget DIdentifier idTime Interval THash Chain: H(C,H( B, MACKAD( )))Node List: B, CMAC list: MACKBi ( ),MACKCi ( )
3
Packet broadcasted by C
Route REQUEST Message:Initiator ATarget DIdentifier idTime Interval THash Chain: H( B, MACKAD( ))Node List: BMAC list: MACKBi ( )
2Packet broadcasted by B
Route REQUEST Message:Initiator ATarget DIdentifier id Time Interval THash Chain: MACKAD ( )Node List: emptyMAC list : empty
Packet broadcasted by A
1
Securing Wireless Ad Hoc Networks PRESENTATION - 28Valérie Gayraud & Bruno Tharon
Route REPLY Message:Target D Initiator ATime Interval TNode List: B, CMAC list: MACKBi ( ),MACKCi ( )Target MAC: MACKDA ( ),Key List: empty
1Packet from D to C
Route REPLY Message:Target D Initiator ATime Interval TNode List: B, CMAC list: MACKBi ( ),MACKCi ( )Target MAC: MACKDA ( ),Key List: KCi
2
Packet from C to B
Route REPLY Message:Target D Initiator ATime Interval TNode List: B, CMAC list: MACKBi ( ),MACKCi ( )Target MAC: MACKDA ( ),Key List: KCi, KBi
3
Packet from B to A
Ariadne: ROUTE REPLY
Securing Wireless Ad Hoc Networks PRESENTATION - 29Valérie Gayraud & Bruno Tharon
Route ERROR Message:Sending Address BReceiving Adress ATime IntervalError MAC: MACKBi ( )Recent TESLA key: KBi’
3Packet from B to A
Data Packets A ? C
1
Ariadne: ROUTE ERROR
Broken link2
Securing Wireless Ad Hoc Networks PRESENTATION - 30Valérie Gayraud & Bruno Tharon
A Secure Routing ProtocolAriadne ? Evaluation
• Stability of route (Tested twice)
• Less throughput– Due to slower route discovery– Route error processing delayed (TESLA)
• 26 % more overhead than non optimized DSR
• Slower route discovery with TESLA– Delays due to delayed key disclosure
Securing Wireless Ad Hoc Networks PRESENTATION - 31Valérie Gayraud & Bruno Tharon
Agenda– Goal of the project– What is a wireless ad hoc network?• Introduction
• Security Issues Analysis
– Risk analysis– Results
• Proposed Solutions
– Models from literature– Securing routing– A specific solution: Ariadne
• Conclusion – Project follow-up– Personal comments
Securing Wireless Ad Hoc Networks PRESENTATION - 32Valérie Gayraud & Bruno Tharon
Planning
November 2002
December2002
January2003
February2003
March2003
Draft report delivery01/31/2003
Final report delivery02/28/2003
Presentation 03/11//2003
Kick off meeting Held 11/19/2002
Forecasted Milestones
Achieved Milestones
Final report delivery03/10/2003
Presentation 03/12//2003
Kick off meeting Held 11/19/2002
Draft report review01/14/2003
Draft report review02/24/2003
Draft report delivery12/20/2002
Forecast: 1 day/week for 14 weeks, 14 pers/days: 28 days workload
Effective: Twice more time spent ? 30 pers/days: 60 days workload
Securing Wireless Ad Hoc Networks PRESENTATION - 33Valérie Gayraud & Bruno Tharon
• Installation and Configuration– Free BSD 4.7, Linux Suse 8.0,– Windows 98, XP,– 802.11 Aironet and D-Link cards,
Conclusion: Achieved Work
• 802.11 Protocol Study– Sniffers installation (BSD Airtools,
Ethereal)– Frames analysis,
• Programming and test– “Prismtodump” source code analysis,– Denial of Service Implementation. (To Do)
Securing Wireless Ad Hoc Networks PRESENTATION - 34Valérie Gayraud & Bruno Tharon
• A Challenge for the Security– Authentication of nodes– Authentication of management messages– Several models, few applications
Securing Wireless Ad Hoc NetworksConclusion
• Routing functions– Reutilization of wired oriented protocols
• Efficiency-oriented• Security not taken into account
– Adaptation of current protocols– Immaturity
• Trade-off between security and autonomy/efficiency
Securing Wireless Ad Hoc Networks PRESENTATION - 35Valérie Gayraud & Bruno Tharon
• Work onto existing routing implementation (OSLR from INRIA -> Linux & Windows 2000),
• Can we use IPSEC (VPN) ?
• Take time to study all routing protocols
• Trust Relationship Models,
• Intrusion detection in ad hoc networks
Conclusion : Future work
Any Questions ?
Securing Wireless Ad Hoc Networks PRESENTATION - 37Valérie Gayraud & Bruno Tharon
GlossaryAP Access Point AODV Ad hoc On-demand D istance VectorART Autorité de Régulation des TélécommunicationsAT-GDH Arbitrary Topology Generalization of D iffie-HellmanBD-ADDR Bluetooth Device ADDRessBER Bit Error RateBRAN Broadband Radio Access Networks (Group of work within
ETSI)CRC Cyclic Redundancy CheckCSMA/CA Carrier Sense Multiple Access / Carrier AvoidanceDSR Dynamic Source RoutingDVMRP Distance Vector Multicast Routing ProtocolEAP Extensible Authentication ProtocolEBIOS Expression des Besoins et Identification des Objectifs de
Sécurité French approach, stands for security requirements and identification of the target of security
ETSI European Telecommunications Standards InstituteEY-NPMA Elimination Yield None Pre-emptive Priority Multiple
AccessFCC Federal Communications CommissionFSK Frequency-Shift KeyingGDH Generalization of D iffie-HellmanGMSK Gaussian Minimum Shift KeyingGPRS General Packet Radio ServiceHiperLAN High Performance Local Area NetworkIDS Intrusion Detection SystemIEEE Institute of Electrical and Electronics EngineersIETF Internet Engineering Task ForceIrDA Infrared Data AssociationIrLAP Infrared Link Access ProtocolISM Industrial, Scientific and Medical
IV Init VectorMAC Medium Access ControlMANET Mobile Ad hoc NETworkMAODV Multicast Ad hoc On-demand D istance VectorMPR Multi Point RelayNSA National Security AgencyOLSR Optimized Link State RoutingPAN Personal Area NetworkPDA Personal D igital AssistantPGP Pretty Good PrivacyPRNG Pseudo RaNdom GeneratorQoP Quality of ProtectionRIP Routing Internet ProtocolRREQ Route REQuest RREP Route REPlyRERR Route ERRorRSN Robust Security NetworksSAR Security-Aware ad hoc RoutingSIG Special Interest GroupSNMP Simple Network Management ProtocolSRR Send Route RequestSWAP Shared Wireless Access ProtocolTDMA Time D ivision Multiple AccessTESLA Time Efficient Stream Loss-tolerant AuthenticationUMTS Universal Mobile TelecommunicationsWECA Wireless Ethernet Compatibility AllianceWEP Wired Equivalent Privacy ProtocoleWi-Fi Wireless FidelityWLAN Wireless Local Area NetworkWPAN Wireless Personal Area Network
Securing Wireless Ad Hoc Networks PRESENTATION - 38Valérie Gayraud & Bruno Tharon
What is a Wireless Ad Hoc Network ?
AB
C
D
Then, nodes are capable to communicate with each other or route data for another nodes
Node A : laptop
Node C : computer embedded in a car
Node B : palm pilotNode D : laptop
Communicationcut off but maintains
through B
Securing Wireless Ad Hoc Networks PRESENTATION - 39Valérie Gayraud & Bruno Tharon
Possible Application : Solve a lack of coverage in UMTS network
NodeB
NodeB
NodeBNodeB
NodeB
NodeB
Securing Wireless Ad Hoc Networks PRESENTATION - 40Valérie Gayraud & Bruno Tharon
Annex: Authentication / Key Agreement
S1
S4
S4
S2
S3
Key = ? S1S2S3S4
Distributory
Contributory
Key = H(PWD)
Pwd
PwdPwd
Pwd
Pwd