ICT-2007-216676
ECRYPT II
European Network of Excellence in Cryptology II
Network of Excellence
Information and Communication Technologies
Main Computational Assumptions in Cryptography
D.MAYA.3
Due date of deliverable: 1 February 2010
Actual submission date: 29 April 2010
Start date of project: 1 August 2008
Duration: 4 years
Lead contractor: Katholieke Universiteit Leuven (KUL)
Revision 1.0
Project co-funded by the European Commission within the 7th Framework Programme
Dissemination Level
PU Public
PP Restricted to other programme participants (including the Commission services)
RE Restricted to a group specified by the consortium (including the Commission services)
CO Confidential, only for members of the consortium (including the Commission services)
X
ECRYPT IIECRYPT II
Main Computational Assumptions in Cryptography
Editor
Fr´e Vercauteren (K.U.Leuven)
Contributors
Naomi Benger (Shannon Institute),
Dario Catalano (UNICT), Manuel Charlemagne (Shannon Institute),
David Conti (Shannon Institute), Biljana Cubaleska (RUB),
Hernando Fernando (Shannon Institute), Dario Fiore (UNICT),
Steven Galbraith (RHUL), David Galindo (Uni.Lu),
Jens Hermans (K.U.Leuven), Vincenzo Iovino (UNISA),
Tibor Jager (RUB), Markulf Kohlweiss (K.U.Leuven),
Benoit Libert (UCL), Richard Lindner (TUD),
Hans Loehr (RUB), Danny Lynch (Shannon Institute),
Richard Moloney (Shannon Institute), Khaled Ouafi (EPFL),
Benny Pinkas (University of Haifa), Frantisek Polach (Shannon Institute),
Mario Di Raimondo (UNICT), Markus R¨uckert (TUD),
Michael Schneider (TUD), Vijay Singh (Shannon Institute),
Nigel Smart (UNIVBRIS), Martijn Stam (EPFL),
Fr´e Vercauteren (K.U.Leuven), Jorge Villar Santos (UPC),
Steve Williams (UNIVBRIS)
29 April 2010
Revision 1.0
The work described in this report has in part been supported by the Commission of the European Com-
munities through the ICT program under contract ICT-2007-216676. The information in this document is
provided as is, and no warranty is given or implied that the information is fit for any particular purpose. The
user thereof uses the information at its sole risk and liability.
Contents
1 Introduction
2 Discrete logarithm problem
1. DLP: discrete logarithm problem . . . . . . . . . . . . . . . . . . . . . . .
2. CDH: computational Diffie-Hellman problem . . . . . . . . . . . . . . . .
3. SDH: static Diffie-Hellman problem . . . . . . . . . . . . . . . . . . . . . .
4. gap-CDH: Gap Diffie-Hellman problem . . . . . . . . . . . . . . . . . . . .
5. DDH: decision Diffie-Hellman problem . . . . . . . . . . . . . . . . . . . .
6. Strong-DDH: strong decision Diffie-Hellman problem . . . . . . . . . . . .
7. sDDH: skewed decision Diffie-Hellman problem . . . . . . . . . . . . . . .
8. PDDH: parallel decision Diffie-Hellman problem . . . . . . . . . . . . . .
9. Square-DH: Square Diffie-Hellman problem . . . . . . . . . . . . . . . . .
10. l-DHI: l-Diffie-Hellman inversion problem . . . . . . . . . . . . . . . . . .
11. l-DDHI: l-Decisional Diffie-Hellman inversion problem . . . . . . . . . .
12. REPRESENTATION: Representation problem . . . . . . . . . . . . . . .
13. LRSW: LRSW Problem . . . . . . . . . . . . . . . . . . . . . . . . . . .
14. Linear: Linear problem . . . . . . . . . . . . . . . . . . . . . . . . . . . .
15. D-Linear1: Decision Linear problem (version 1)
. . . . . . . . . . . . . .
16. l-SDH: l-Strong Diffie-Hellman problem . . . . . . . . . . . . . . . . . . .
17. c-DLSE: Discrete Logarithm with Short Exponents
. . . . . . . . . . . .
18. CONF: (conference-key sharing scheme)
. . . . . . . . . . . . . . . . . .
19. 3PASS: 3-Pass Message Transmission Scheme
. . . . . . . . . . . . . . .
20. LUCAS: Lucas Problem . . . . . . . . . . . . . . . . . . . . . . . . . . .
21. XLP: x-Logarithm Problem . . . . . . . . . . . . . . . . . . . . . . . . . .
22. MDHP: Matching Diffie-Hellman Problem . . . . . . . . . . . . . . . . .
23. DDLP: Double Discrete Logarithm Problem . . . . . . . . . . . . . . . .
24. rootDLP: Root of Discrete Logarithm Problem . . . . . . . . . . . . . . .
25. n-M-DDH: Multiple Decision Diffie-Hellman Problem . . . . . . . . . . .
26. l-HENSEL-DLP: l-Hensel Discrete Logarithm Problem . . . . . . . . . .
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27. DLP(Inn(G)): Discrete Logarithm Problem over Inner Automorphism
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Group
28. IE: Inverse Exponent
. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
29. TDH: The Twin Diffie-Hellman Assumption . . . . . . . . . . . . . . . .
30. XTR-DL: XTR discrete logarithm problem . . . . . . . . . . . . . . . . .
31. XTR-DH: XTR Diffie-Hellman problem . . . . . . . . . . . . . . . . . . .
32. XTR-DHD: XTR decision Diffie-Hellman problem . . . . . . . . . . . . .
33. CL-DLP: discrete logarithms in class groups of imaginary quadratic orders
34. TV-DDH: Tzeng Variant Decision Diffie-Hellman problem . . . . . . . .
35. n-DHE: n-Diffie-Hellman Exponent problem . . . . . . . . . . . . . . . .
3 Factoring
36. FACTORING: integer factorisation problem . . . . . . . . . . . . . . . .
37. SQRT: square roots modulo a composite
. . . . . . . . . . . . . . . . . .
38. CHARACTERd: character problem . . . . . . . . . . . . . . . . . . . . .
39. MOVAd: character problem . . . . . . . . . . . . . . . . . . . . . . . . .
40. CYCLOFACTd: factorisation in Z[θ]
41. FERMATd: factorisation in Z[θ]
42. RSAP: RSA problem . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . .
43. Strong-RSAP: strong RSA problem . . . . . . . . . . . . . . . . . . . . .
44. Difference-RSAP: Difference RSA problem . . . . . . . . . . . . . . . . .
45. Partial-DL-ZN2P: Partial Discrete Logarithm problem in Z∗
46. DDH-ZN2P: Decision Diffie-Hellman problem over Z∗
47. Lift-DH-ZN2P: Lift Diffie-Hellman problem over Z∗
48. EPHP: Election Privacy Homomorphism problem . . . . . . . . . . . . .
. . . . . . . . . . .
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n2
n2
n2
49. AERP: Approximate e-th root problem . . . . . . . . . . . . . . . . . . .
50. l-HENSEL-RSAP: l-Hensel RSA . . . . . . . . . . . . . . . . . . . . . . .
51. DSeRP: Decisional Small e-Residues in Z∗
52. DS2eRP: Decisional Small 2e-Residues in Z∗
53. DSmallRSAKP: Decisional Reciprocal RSA-Paillier in Z∗
54. HRP: Higher Residuosity Problem . . . . . . . . . . . . . . . . . . . . . .
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55. ECSQRT: Square roots in elliptic curve groups over Z/nZ . . . . . . . .
56. RFP: Root Finding Problem . . . . . . . . . . . . . . . . . . . . . . . . .
57. phiA: PHI-Assumption . . . . . . . . . . . . . . . . . . . . . . . . . . . .
58. C-DRSA: Computational Dependent-RSA problem . . . . . . . . . . . .
59. D-DRSA: Decisional Dependent-RSA problem . . . . . . . . . . . . . . .
60. E-DRSA: Extraction Dependent-RSA problem . . . . . . . . . . . . . . .
61. DCR: Decisional Composite Residuosity problem . . . . . . . . . . . . .
62. CRC: Composite Residuosity Class problem . . . . . . . . . . . . . . . .
63. DCRC: Decisional Composite Residuosity Class problem . . . . . . . . .
64. GenBBS: generalised Blum-Blum-Shub assumption
. . . . . . . . . . . .
4 Product groups
65. co-CDH: co-Computational Diffie-Hellman Problem . . . . . . . . . . . .
66. XDDH: External Decision Diffie-Hellman Problem . . . . . . . . . . . . .
67. D-Linear2: Decision Linear Problem (version 2)
. . . . . . . . . . . . . .
68. FSDH: Flexible Square Diffie-Hellman Problem . . . . . . . . . . . . . .
69. KSW1: Assumption 1 of Katz-Sahai-Waters
. . . . . . . . . . . . . . . .
5 Pairings
70. BDHP: Bilinear Diffie-Hellman Problem . . . . . . . . . . . . . . . . . .
71. DBDH: Decision Bilinear Diffie-Hellman problem . . . . . . . . . . . . .
72. l-BDHI: l-Bilinear Diffie-Hellman Inversion Problem . . . . . . . . . . . .
73. l-DBDHI: l-Bilinear Decision Diffie-Hellman Inversion Problem . . . . .
74. l-wBDHI: l-weak Bilinear Diffie-Hellman Inversion Problem . . . . . . .
75. l-wDBDHI: l-weak Decisional Bilinear Diffie-Hellman Inversion Problem
76. KSW2: Assumption 2 of Katz-Sahai-Waters
. . . . . . . . . . . . . . . .
77. MSEDH: Multi-sequence of Exponents Diffie-Hellman Assumption . . . .
6 Lattices
6.1 Main Lattice Problems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
78. SVPγ
79. CVPp
p: (Approximate) Shortest vector problem . . . . . . . . . . . . . .
γ: (Approximate) Closest vector problem . . . . . . . . . . . . . . .
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80. GapSVPp
γ: Decisional shortest vector problem . . . . . . . . . . . . . . .
γ: Decisional closest vector problem . . . . . . . . . . . . . . . .
6.2 Modular Lattice Problems . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
81. GapCVPp
82. SISp(n, m, q, β): Short integer solution problem . . . . . . . . . . . . . .
83. ISISp(n, m, q, β): Inhomogeneous short integer solution problem . . . . .
6.3 Miscellaneous Lattice Problems . . . . . . . . . . . . . . . . . . . . . . . . . .
84. USVPp(n, γ): Approximate unique shortest vector problem . . . . . . . .
85. SBPp(n, γ): Approximate shortest basis problem . . . . . . . . . . . . . .
86. SLPp(n, γ): Approximate shortest length problem . . . . . . . . . . . . .
87. SIVPp(n, γ): Approximate shortest independent vector problem . . . . .
88. hermiteSVP: Hermite shortest vector problem . . . . . . . . . . . . . . .
89. CRP: Covering radius problem . . . . . . . . . . . . . . . . . . . . . . . .
6.4
Ideal Lattice Problems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
90.
91. Ideal-SISf,p
Ideal-SVPf,p
γ : (Approximate) Ideal shortest vector problem / Shortest
polynomial problem . . . . . . . . . . . . . . . . . . . . . . . . . . . .
q,m,β: Ideal small integer solution problem . . . . . . . . . . . .
7 Miscellaneous Problems
92. KEA1: Knowledge of Exponent assumption
. . . . . . . . . . . . . . . .
93. MQ: Multivariable Quadratic equations . . . . . . . . . . . . . . . . . . .
94. CF: Given-weight codeword finding
. . . . . . . . . . . . . . . . . . . . .
95. ConjSP: Braid group conjugacy search problem . . . . . . . . . . . . . .
96. GenConjSP: Generalised braid group conjugacy search problem . . . . .
97. ConjDecomP: Braid group conjugacy decomposition problem . . . . . . .
98. ConjDP: Braid group conjugacy decision problem . . . . . . . . . . . . .
99. DHCP: Braid group decisional Diffie-Hellman-type conjugacy problem .
100. ConjSearch: (multiple simlutaneous) Braid group conjugacy search prob-
lem . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
101. SubConjSearch: subgroup restricted Braid group conjugacy search prob-
lem . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
102. LINPOLY : A linear algebra problem on polynomials
. . . . . . . . . .
103. HFE-DP: Hidden Field Equations Decomposition Problem . . . . . . .
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