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An Ultra-lightweight Authentication Protocol in RFID

Speaker:魏家惠

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Outline

• Introduction– Environment Definition– Authenticate Analysis

• Related Work– First paper– Important paper between 2006 ~ 2009– Recently paper 2009– Security Analysis

• Comments

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Environment Definition• Chien ‘s four class in RFID

– Full-fledged• Symmetric encryption• Public key algorithms

– Simple • Random number generator • One-way hashing function

– Lightweight • Random number generator• Cyclic Redundancy Code checksum

– Ultralightweigh• XOR, AND, OR, Rot

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Authenticate Analysis

• Tag Identification • Mutual Authentication• Index-Pseudonym Updating• Key Updating

– Mutual authentication – Data integrity– Tag anonymity– Tracking– Data confidentiality– Forward security– Replay attack– Man-in-the-middle attack– de-synchronization attack

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First paper (M2AP scheme)

• [2006] M2AP A Minimalist Mutual Authentication Protocol for Low-cost RFID Tags, In: LNCS, vol. 4159. Springer. pp. 912-923,2006.

Reader Tags1. hello

2. IDS

ID, IDS, K1, K2, K3

ID, IDS, K1, K2, K3

3. A B C∥ ∥

4. D E∥

A=IDS K1 n1♁ ♁

B=(IDS ^ K2)ˇn1

C=IDS+K3+n2

D=(IDSˇK4) ^ n2

E=(IDS+ID) n1♁

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Second paper (LMAP scheme)

• [2006]LMAP A Real Lightweight Mutual Authentication Protocol for Low-cost RFID tags, in Proceedings of the 2nd Workshop on RFID Security, 2006.

Reader Tags1. hello

2. IDS

(ID, IDS, K1, K2, K3)next

(ID, IDS, K1, K2, K3)old

3. A B C∥ ∥

4. D

(ID, IDS, K1, K2, K3)next

(ID, IDS, K1, K2, K3)old

A=IDS K1 n1♁ ♁

B=(IDSˇK2)+n1

C=IDS+K3+n2

D=(IDS+ID) n1 n2♁ ♁

M2AP

A=IDS K1 n1♁ ♁

B=(IDS ^ K2)ˇn1

C=IDS+K3+n2

D=(IDSˇK4) ^ n2

E=(IDS+ID) n1♁

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Security analysis of LMAP and M2AP (Li and Wang’s Scheme)

• [2007] Security Analysis of Two Ultra lightweight RFID Authentication Protocol, International Federation for Information Processing, Vol. 232, pp. 109-120, 2007.

• Vulnerabilities of LMAP and M2AP – de-synchronization

• Changing message C

– Full-disclosure

Reader

Tags

1. hello

2. IDS

3. A B∥ ∥C’

4. D’

A=IDS K1 n1♁ ♁

B=(IDS V K2)+n1

C=IDS+K3+n2’

D=(IDS+ID) n1 n2’♁ ♁

C=(IDS+K3)+n2

D=(IDS+ID) n1 n2♁ ♁C-IDS-K3=(IDS+ID) n1 D♁ ♁

Cnew=(IDS+K3)+n2new

Dnew=(IDS+ID) n1 n2♁ ♁ newCnew-IDS-K3=(IDS+ID) n1 D♁ ♁ new

Cnew-C=(IDS+ID)♁Dnew-(IDS+ID)♁n1 D♁

(1)

(2)

(1) - (2)

x♁a = x♁b + c mod 296 96bits/4=24 (2 24 — 1) times

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Countermeasures of Li and Wang’s Scheme (cont.)

• Countermeasures– Sending `D (to solve full-disclosure attack)

• The tag always send a message to fool the attacker. • If the reader is authenticated, it sends D=(IDS+ID)♁n1♁n2 ; otherwise , it sends

D’=(IDS+ID)♁n2

– Storing status (to solve incomplete protocol)• The reader and the tag keep the status and the random number of the protocol• A status bit S=0 → the protocol is completed (synchronized)• A status bit S=1 → the protocol is uncompleted (desynchronized)• After that can updating n1 and n2

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Security analysis of Li and Wang’s scheme

• [2007]Security of ultra-lightweight RFID authentication protocols and its improvements, ACM SIGOPS Operating Systems Review, Vol.41 Issue 4, 2007.

• Vulnerabilities of Li Wang’s attacks – Sending `D (to solve full-disclosure attack)

• modify phase 3: successfully authenticate

• response D=(IDS+ID)♁n1♁n2

• next, send A’ B C∥ ∥ authentication will fail

• response D’=(IDS+ID)♁n2

• D’♁D get n1

A B C∥ ∥

D=(IDS+ID)♁n1♁n2

A’ B C∥ ∥

D’=(IDS+ID)♁n2

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Security analysis of Li and Wang’s attacks (cont.)

• Countermeasures– Sending `D (to solve full-disclosure attack)

• The tag extracted value (n1, n1’, n2) from A B C∥ ∥• Outputs the value shift(n1,n1’)♁shift(n1’,n2) is random value

• D=(IDS+ID)♁ shift(n1,n1’) ♁shift(n1’,n2)

– Full-disclosure• modify phase 5: (1) set n1new=0. (2) set C1

new=Cnew+1

• n2[1]=0, n2=000…00, n2♁(n2+1)=000…01• n2[1]=1, n2=00…01…1, n2♁(n2+1)=000…01…1• The attacker can determine iє[0,95] , i+1 < (224-1)

A=IDS K1 n1♁ ♁

B=(IDSˇK2)+n1

C=IDS+K3+n2

D=(IDS+ID) n1 n2♁ ♁

Anew=IDS♁K1Bnew=IDSˇK2Dnew=(IDS♁ID) ♁n2

D1new=(IDS♁ID) ♁n2+1

Dnew ♁ D1new= (n2+1)♁n2

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Important paper

• [2007] SASI A New Ultra-lightweight RFID Authentication protocol providing strong authentication and strong integrity, IEEE Transactions on Dependable and Secure Computing

4(4), pp. 337-340, October, 2007.

Reader Tags1. hello

2. IDS

ID, IDS, K1, K2, K3

ID, IDS, K1, K2, K3

3. A B C∥ ∥

4. D

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Cryptanalysis of SASI

• [2008]Cryptanalysis of a New Ultralightweight RFID Authentication Protocol-SASI, IEEE Transactions on Dependable and Secure Computing, Vol. 6, No. 4, pp.316-320, 2008.

8bits固定值” E0”8bits IC廠商的編碼 (MSB)48bits廠商所定的獨一序號 (LSB)

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Security analysis of SASI (cont.)

• [2009] On the Security of Chien's Ultra-Lightweight RFID Authentication Protocol, IEEE Transactions on Dependable and Secure Computing, pp.1-3, 2009.

Reader

Tags

1. hello

2. IDS

3. A’ B’ C’∥ ∥

4. D

ID, IDS1, K11, K21, K31

ID, IDS3, K13, K23, K33

A’ B’ C’∥ ∥

Attacker

ID, IDS1, K11, K21, K31

ID, IDS2, K12, K22, K32

1st round

2st round

NormalID, IDS1, K11, K21, K31

ID, IDS3, K13, K23, K33

ID, IDS0, K10, K20, K30

ID, IDS1, K11, K21, K31

ID, IDS0, K10, K20, K30

ID, IDS1, K11, K21, K31

ID, IDS0, K10, K20, K30

ID, IDS1, K11, K21, K31

3. A’’ B’’ C’’∥ ∥

3st round

1. hello

2. IDS1

3. A’ B’ C’∥ ∥4. D’

ID, IDS1, K11, K21, K31

ID, IDS3, K13, K23, K33

ID, IDS1, K11, K21, K31

ID, IDS2, K12, K22, K32

Attacker

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Recently paper• [2009] An Ultra Light Authentication Protocol Resistant to

Passive Attacks under the Gen-2 Specification, Journal of Information Science and Engineering 25(1), pp.33-57, 2009. – Assumption: backward and forward channel can be passively

listened by an attacker.– Min-in-the-middle and other active attacks are not feasible

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Comments

• [2009] On the Security of Chien's Ultra-Lightweight RFID Authentication Protocol, IEEE Transactions on Dependable and Secure Computing, pp.1-3, 2009. – 3st is not authenticated by the reader– Because the reader generate new n2, it not equal to B’ and C’

• [2009] An Ultra Light Authentication Protocol Resistant to Passive Attacks under the Gen-2 Specification, Journal of Information Science and Engineering 25(1):33-57, 2009.– Cryptanalysis of ULAP is the same as LMAP

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Thank you