Improving Security and Reliability in Merkle Tree-Based Online Data Authentication with Leakage Resilience
Abstract
:1. Introduction
- We analyze potential information leakage during the online verification process. It includes partial information of the Merkle tree and size information, which weaken the security and reliability of authentication (Section 3).
- We evaluate efficiency of the proposed scheme by implementing it in a real-world application. It shows that our approach can flexibly be adjusted to required system resources with minimal overhead. Nonetheless, it still supports leakage resilience that was not guaranteed in previous research (Section 6).
2. Merkle Tree-Based Authentication
- Prover is an entity who attempts to convince the other party (i.e., the verifier ) that it owns all of the data. To converve network bandwidth, the prover sends a small piece of verifiable information instead of all of the content.
- Verifier is another entity who tries to determine whether prover ’s claim is correct or not. To reduce storage requirements, the verifier usually stores only the value of the root node of the Merkle tree instead of all nodes of the tree.
3. Information Leakage Analysis of Merkle Tree-Based Authentication Schemes
3.1. Analysis of Merkle Tree-Based Authentication
3.1.1. Leakage of Data Size Information
3.1.2. Leakage of Merkle Tree Hash Values
3.2. Previous Schemes and Their Vulnerabilities
3.2.1. Generic Merkle Tree-Based Authentication
3.2.2. Authentication without a Merkle Tree
Algorithm 1 Randomized online authentication exploiting a hardcore function |
3.2.3. Merkle Tree-Based Authentication of Encrypted Data
3.2.4. Merkle Tree-Based Authentication with Transmission in Encrypted Form
Algorithm 2 Merkle tree-based online authentication with encrypted communication |
4. Randomized Online Authentication
4.1. Adversarial Model
4.2. Goal
- Prevention of size information leakage: The authentication mechanism should block the outflow of information about the size of the target data, which can be used by adversaries to select and predict the required number of authentication proofs.
- Prevention of replay attacks: The protocol should not allow adversaries to launch replay attacks, in which a collected valid set of authentication proofs are used in subsequent authentication requests. In other words, the adversary cannot learn any information from the disclosed information via public channels during the authentication process.
- Minimal requctions in efficiency: The effective handling of side channels should be achieved with acceptable computation and communication overhead, maintaining the advantages of the Merkle tree-based approach.
- Compatability: Given that the Merkle tree-based approach is widely deployed in industry and academia due to its intuitive nature and ease of utilization, the proposed approach should be applicable to existing uses. This includes adaptability to lightweight devices with limited resources and restrictions on the installation of additional libraries depending on the system architecture, such as IoT terminal devices and sensors.
4.3. Construction
Algorithm 3 Merkle tree-based online authentication with randomized input |
4.3.1. Authentication Initiation
4.3.2. Randomized Challenge Generation
4.3.3. Original Challenge Restoration
4.3.4. Proof Generation
4.3.5. Proof Obfuscation
4.3.6. (Original) Proof Restoration
4.3.7. Proof Verification
5. Security Analysis
5.1. Security of Merkle Tree-based Authentication
5.2. Security of the Proposed Scheme
5.2.1. Security of One-time Secret Delivery
5.2.2. Security of the Proposed Scheme
6. Efficiency Analysis
6.1. Experimental Environment
6.2. Computation Overhead
6.2.1. Authentication Based on Merkle Tree
6.2.2. Authentication Based on the Hardcore Function
6.2.3. Authentication Based on Merkle Tree with Transmission in Encrypted Form
6.2.4. Authentication Based on the Proposed Approach
6.2.5. Analysis of Computation Overhead
6.3. Communication Overhead
7. Conclusions
Author Contributions
Funding
Conflicts of Interest
References
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Notation | Description |
---|---|
Cryptographic hash function | |
Size of the hash value (in bits) | |
n | Number of data blocks for the entire data D |
Merkle tree constructed from data D | |
Root node in the Merkle tree | |
h | Height of the Merkle tree |
L | Required length of the sibling path in the authentication proof |
Value of the given node N | |
Sibling node in the sibling path for the given node N | |
i-th element in sequence A (cardinality) | |
Number of elements in set A | |
Random selection of element a in set A | |
Assignment of the result of the deterministic algorithm (operation) B to b | |
Assignment of the result of the probabilistic algorithm (operation) B to b |
100 B | 1 KB | 10 KB | 100 KB | 1 MB | 10 MB | 100 MB | 1 GB | |
---|---|---|---|---|---|---|---|---|
Merkle tree generation | 0.00461 | 0.01748 | 0.11897 | 1.05451 | 10.67579 | 107.07319 | 1134.07592 | 11,191.59684 |
(0.00062) | (0.00080) | (0.00247) | (0.00723) | (0.09199) | (1.07465) | (19.51252) | (33.31233) | |
Challenge generation | 0.00086 | 0.00086 | 0.00099 | 0.00101 | 0.00100 | 0.00100 | 0.00087 | 0.00087 |
(0.00019) | (0.00017) | (0.00020) | (0.00021) | (0.00021) | (0.00023) | (0.00017) | (0.00016) | |
Sibling path generation | 0.00201 | 0.00389 | 0.00662 | 0.00863 | 0.01101 | 0.01258 | 0.02032 | 0.02273 |
(0.00024) | (0.00066) | (0.00048) | (0.00038) | (0.00059) | (0.00054) | (0.00159) | (0.00168) | |
Verification | 0.00127 | 0.00417 | 0.00937 | 0.01398 | 0.01836 | 0.02369 | 0.02840 | 0.03294 |
(0.00034) | (0.00030) | (0.00077) | (0.00075) | (0.00096) | (0.00149) | (0.00085) | (0.00096) |
100 B | 1 KB | 10 KB | 100 KB | 1 MB | 10 MB | 100 MB | 1 GB | |
---|---|---|---|---|---|---|---|---|
Seed generation | 0.00065 | 0.00075 | 0.00092 | 0.00223 | 0.00313 | 0.00420 | 0.00822 | 0.01068 |
(0.00016) | (0.00018) | (0.00020) | (0.00061) | (0.00037) | (0.00054) | (0.00101) | (0.00119) | |
Pseudorandom bitstring | 0.01106 | 0.01417 | 0.03730 | 0.28324 | 4.12432 | 44.29721 | 450.26368 | 4690.52351 |
generation | (0.00085) | (0.00133) | (0.00351) | (0.02986) | (0.79537) | (8.69847) | (89.4971) | (488.92123) |
Proof generation | 0.04765 | 0.57035 | 7.20359 | 84.95004 | 1058.25365 | 12,523.93617 | 139,315.96462 | 1,666,976.31436 |
(0.00148) | (0.01614) | (0.09508) | (0.86894) | (2.32808) | (8.65474) | (236.08956) | (2663.86754) | |
Verification | 0.00018 | 0.00019 | 0.00022 | 0.00032 | 0.00036 | 0.00036 | 0.00036 | 0.00100 |
(0.00014) | (0.00014) | (0.00013) | (0.00013) | (0.00013) | (0.00013) | (0.00014) | (0.00023) |
100 B | 1 KB | 10 KB | 100 KB | 1 MB | 10 MB | 100 MB | 1 GB | |
---|---|---|---|---|---|---|---|---|
Parameter | 9468.19790 | 9538.16482 | 9794.65946 | 9532.98866 | 9452.51795 | 9727.44050 | 9064.76798 | 9633.54744 |
generation | (8493.82876) | (8975.20449) | (9175.01323) | (8829.14856) | (8759.71474) | (9374.65954) | (7981.16155) | (8863.74385) |
Partial key | 4.80688 | 4.79883 | 4.78975 | 4.79192 | 4.80195 | 4.80006 | 4.81253 | 4.96501 |
generation | (0.18776) | (0.18395) | (0.18719) | (0.18367) | (0.18475) | (0.18142) | (0.19221) | (0.25943) |
Key | 4.57732 | 4.57399 | 4.56398 | 4.56755 | 4.57577 | 4.57745 | 4.57501 | 4.57433 |
agreement | (0.13962) | (0.14449) | (0.14221) | (0.15151) | (0.15099) | (0.14848) | (0.14461) | (0.14200) |
Challenge | 0.00087 | 0.00098 | 0.00091 | 0.00088 | 0.00100 | 0.00087 | 0.00099 | 0.00087 |
generation | (0.00018) | (0.00020) | (0.00020) | (0.00016) | (0.00021) | (0.00016) | (0.00023) | (0.00018) |
Encryption of | 0.02674 | 0.02647 | 0.02668 | 0.02702 | 0.03341 | 0.03457 | 0.03739 | 0.05227 |
the challenge | ( 0.00145) | (0.00140) | (0.00117) | (0.0013) | (0.00210) | (0.00235) | (0.00323) | (0.00281) |
Decryption of | 0.01458 | 0.01567 | 0.01597 | 0.01776 | 0.01967 | 0.02292 | 0.02444 | 0.02568 |
the challenge | (0.00068) | (0.00065) | (0.00042) | (0.00088) | (0.00118) | (0.00097) | (0.00064) | (0.00066) |
Merkle tree | 0.00324 | 0.01570 | 0.11664 | 1.05112 | 10.55169 | 106.34833 | 1072.881132 | 11,196.73308 |
generation | (0.00024) | (0.00043) | (0.00184) | (0.03182) | (0.08447) | (0.36833) | (6.69879) | (33.06858) |
Sibling path | 0.00271 | 0.00429 | 0.00655 | 0.00808 | 0.01018 | 0.01172 | 0.01773 | 0.02247 |
generation | (0.00033) | (0.00042) | (0.00047) | (0.00054) | (0.00079) | (0.00047) | (0.00100) | (0.00101) |
Encryption of | 0.01639 | 0.01751 | 0.01866 | 0.02067 | 0.02978 | 0.04813 | 0.05219 | 0.05405 |
the sibling path | (0.00061) | (0.00043) | (0.00089) | (0.00117) | (0.00323) | (0.00177) | (0.00118) | (0.00357) |
Decryption of | 0.01782 | 0.01776 | 0.01895 | 0.01714 | 0.01790 | 0.01957 | 0.02026 | 0.02090 |
the sibling path | (0.00061) | (0.00071) | (0.00062) | (0.00085) | (0.00058) | (0.00102) | (0.00080) | (0.00129) |
Verification | 0.00130 | 0.00454 | 0.00981 | 0.01408 | 0.01836 | 0.02378 | 0.02848 | 0.03252 |
(0.00018) | (0.00041) | (0.00078) | (0.00091) | (0.00112) | (0.00121) | (0.00088) | (0.00041) |
100 B | 1 KB | 10 KB | 100 KB | 1 MB | 10 MB | 100 MB | 1 GB | |
---|---|---|---|---|---|---|---|---|
Requested proof length | 49.04100 | 50.84400 | 52.70700 | 52.58500 | 52.22300 | 51.67100 | 50.86000 | 50.81600 |
(27.97269) | (28.63403) | (27.93591) | (28.83915) | (28.47626) | (28.3989) | (27.28825) | (28.78524) | |
Merkle tree generation | 0.00299 | 0.01417 | 0.11407 | 1.04286 | 10.53377 | 106.27209 | 1081.34281 | 11,178.68500 |
(0.00098) | (0.00324) | (0.03135) | (0.29979) | (3.02505) | (30.96492) | (320.58949) | (354.27592) | |
Challenge generation | 0.00216 | 0.00226 | 0.00247 | 0.00243 | 0.00216 | 0.00240 | 0.00243 | 0.00238 |
(0.00068) | (0.00067) | (0.00062) | (0.00053) | (0.00070) | (0.00056) | (0.00059) | (0.00068) | |
Sibling path generation | 0.00000 | 0.00000 | 0.00000 | 0.00000 | 0.00002 | 0.00002 | 0.00003 | 0.00002 |
(0.00000) | (0.00000) | (0.00000) | (0.00000) | (0.00000) | (0.00000) | (0.00000) | (0.00000) | |
Sibling path obfuscation | 0.04547 | 0.06643 | 0.10507 | 0.13948 | 0.17899 | 0.23363 | 0.26413 | 0.29186 |
(0.00596) | (0.00338) | (0.01607) | (0.01782) | (0.02655) | (0.03630) | (0.04581) | (0.06181) | |
Random bitstring padding | 0.89665 | 0.87894 | 0.85868 | 0.78980 | 0.72994 | 0.66017 | 0.59333 | 0.55448 |
(0.54933) | (0.53655) | (0.53474) | (0.53037) | (0.51176) | (0.49959) | (0.46923) | (0.47786) | |
Mask removal | 0.02384 | 0.04487 | 0.08232 | 0.11417 | 0.14501 | 0.17849 | 0.20863 | 0.23202 |
(0.00310) | (0.00207) | (0.01486) | (0.01715) | (0.02501) | (0.03532) | (0.04438) | (0.06090) | |
Verification | 0.00886 | 0.01602 | 0.01936 | 0.02576 | 0.02953 | 0.03799 | 0.04319 | 0.04763 |
(0.00358) | (0.08621) | (0.00421) | (0.05892) | (0.00504) | (0.01028) | (0.00676) | (0.00924) |
Features | Authentication Based on | |||
---|---|---|---|---|
Merkle Tree | Hardcore Function | Merkle Tree with Encrypted Communication | Proposed Scheme | |
Resilience against size information leakage | X | X | X | O |
Resilience against replay attacks | X | O | O | O |
Requirement for an additional trusted authority | X | X | O | X |
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Share and Cite
Koo, D.; Shin, Y.; Yun, J.; Hur, J. Improving Security and Reliability in Merkle Tree-Based Online Data Authentication with Leakage Resilience. Appl. Sci. 2018, 8, 2532. https://doi.org/10.3390/app8122532
Koo D, Shin Y, Yun J, Hur J. Improving Security and Reliability in Merkle Tree-Based Online Data Authentication with Leakage Resilience. Applied Sciences. 2018; 8(12):2532. https://doi.org/10.3390/app8122532
Chicago/Turabian StyleKoo, Dongyoung, Youngjoo Shin, Joobeom Yun, and Junbeom Hur. 2018. "Improving Security and Reliability in Merkle Tree-Based Online Data Authentication with Leakage Resilience" Applied Sciences 8, no. 12: 2532. https://doi.org/10.3390/app8122532
APA StyleKoo, D., Shin, Y., Yun, J., & Hur, J. (2018). Improving Security and Reliability in Merkle Tree-Based Online Data Authentication with Leakage Resilience. Applied Sciences, 8(12), 2532. https://doi.org/10.3390/app8122532