Skip to main content

How to Build a Trapdoor Function from an Encryption Scheme

  • Conference paper
  • First Online:
Advances in Cryptology – ASIACRYPT 2021 (ASIACRYPT 2021)

Part of the book series: Lecture Notes in Computer Science ((LNSC,volume 13092))

Abstract

In this work we ask the following question: Can we transform any encryption scheme into a trapdoor function (TDF)? Alternatively stated, can we make any encryption scheme randomness recoverable? We propose a generic compiler that takes as input any encryption scheme with pseudorandom ciphertexts and adds a trapdoor to invert the encryption, recovering also the random coins. This universal TDFier only assumes in addition the existence of a hinting pseudorandom generator (PRG). Despite the simplicity, our transformation is quite general and we establish a series of new feasibility results:

  • The first identity-based TDF [Bellare et al. EUROCRYPT 2012] from the CDH assumption in pairing-free groups (or from factoring), thus matching the state of the art for identity-based encryption schemes. Prior works required pairings or LWE.

  • The first collusion-resistant attribute-based TDF (AB-TDF) for all (\(NC^1\), resp.) circuits from LWE (bilinear maps, resp.). Moreover, the first single-key AB-TDF from CDH. To the best of our knowledge, no AB-TDF was known in the literature (not even for a single key) from any assumption. We obtain the same results for predicate encryption.

As an additional contribution, we define and construct a trapdoor garbling scheme: A simulation secure garbling scheme with a hidden “trigger” that allows the evaluator to fully recover the randomness used by the garbling algorithm. We show how to construct trapdoor garbling from the DDH or LWE assumption with an interplay of key-dependent message (KDM) and randomness-dependent message (RDM) techniques.

Trapdoor garbling allows us to obtain alternative constructions of (single-key) AB-TDFs with additional desirable properties, such as adaptive security (in the choice of the attribute) and projective keys. We expect trapdoor garbling to be useful in other contexts, e.g. in case where, upon successful execution, the evaluator needs to immediately verify that the garbled circuit was well-formed.

S. Garg—Supported in part from DARPA/ARL SAFEWARE Award W911NF15C0210, AFOSR Award FA9550-15-1-0274, AFOSR Award FA9550-19-1-0200, AFOSR YIP Award, NSF CNS Award 1936826, DARPA and SPAWAR under contract N66001-15-C-4065, a Hellman Award and research grants by the Okawa Foundation, Visa Inc., and Center for Long-Term Cybersecurity (CLTC, UC Berkeley). The views expressed are those of the author and do not reflect the official policy or position of the funding agencies.

R. Ostrovsky—Supported by DARPA SPAWAR contract N66001-15-C-4065.

This is a preview of subscription content, log in via an institution to check access.

Access this chapter

Chapter
USD 29.95
Price excludes VAT (USA)
  • Available as PDF
  • Read on any device
  • Instant download
  • Own it forever
eBook
USD 89.00
Price excludes VAT (USA)
  • Available as EPUB and PDF
  • Read on any device
  • Instant download
  • Own it forever
Softcover Book
USD 119.99
Price excludes VAT (USA)
  • Compact, lightweight edition
  • Dispatched in 3 to 5 business days
  • Free shipping worldwide - see info

Tax calculation will be finalised at checkout

Purchases are for personal use only

Institutional subscriptions

Notes

  1. 1.

    Our generic conversion starting from any single-key ABE does not preserve property (1) and (3).

  2. 2.

    Although there is some resemblance with our approach, we note that the compiled scheme of [29] is not randomness recoverable unless one starts with a randomness recoverable encryption scheme, which is tautological.

  3. 3.

    One could define the security of the TDF to hold only for uniformly sampled inputs (i.e. one-wayness) however this precludes many interesting applications, such as deterministic and searchable encryption.

  4. 4.

    In Yao’s scheme [30, 37], the key \(k_\mathsf {out, 1} \) is put in the clear in \(\tilde{\mathsf {P}}\) with the corresponding bit 1 for it; we do not put \(k_\mathsf {out, 1} \) in the clear in \(\tilde{\mathsf {P}}\), but rather we encrypt 1 under \(k_\mathsf {out, 1} \) to assert the underlying recovered key corresponds to bit 1; similarly, we encrypt 0 under the output-wire key \(k_\mathsf {out, 0}\) for bit 0.

  5. 5.

    One might complain that the scheme is not randomness recoverable in a strict sense, in that the coins used to sample the group elements are not recovered. We note, however, that in our ABE application, these group elements \(\boldsymbol{\mathsf {g}}\) may be chosen during key-generation time and put in \(\mathsf {pp}\). We ignore these issues for simplicity.

  6. 6.

    The result of [10] concerns a single PKE scheme; in our setting \({\mathsf{SKEBHHO}} \) is just the secret-key version of BHHO, and by choosing the public parameter to be the same across the two schemes, we will have cross KDM security.

  7. 7.

    We remark that this attack does not invalidate any claim made in [28], but rather exemplifies the separation between their approach and ours.

  8. 8.

    The scheme appears in Appendix D in an older version of the paper.

References

  1. Alwen, J., Krenn, S., Pietrzak, K., Wichs, D.: Learning with rounding, revisited. In: Canetti, R., Garay, J.A. (eds.) CRYPTO 2013. LNCS, vol. 8042, pp. 57–74. Springer, Heidelberg (2013). https://doi.org/10.1007/978-3-642-40041-4_4

    Chapter  Google Scholar 

  2. Bellare, M., Boldyreva, A., O’Neill, A.: Deterministic and efficiently searchable encryption. In: Menezes, A. (ed.) CRYPTO 2007. LNCS, vol. 4622, pp. 535–552. Springer, Heidelberg (2007). https://doi.org/10.1007/978-3-540-74143-5_30

    Chapter  Google Scholar 

  3. Bellare, M., et al.: Hedged public-key encryption: how to protect against bad randomness. In: Matsui, M. (ed.) ASIACRYPT 2009. LNCS, vol. 5912, pp. 232–249. Springer, Heidelberg (2009). https://doi.org/10.1007/978-3-642-10366-7_14

    Chapter  Google Scholar 

  4. Bellare, M., Hofheinz, D., Yilek, S.: Possibility and impossibility results for encryption and commitment secure under selective opening. In: Joux, A. (ed.) EUROCRYPT 2009. LNCS, vol. 5479, pp. 1–35. Springer, Heidelberg (2009). https://doi.org/10.1007/978-3-642-01001-9_1

    Chapter  Google Scholar 

  5. Bellare, M., Kiltz, E., Peikert, C., Waters, B.: Identity-based (lossy) trapdoor functions and applications. In: Pointcheval, D., Johansson, T. (eds.) EUROCRYPT 2012. LNCS, vol. 7237, pp. 228–245. Springer, Heidelberg (2012). https://doi.org/10.1007/978-3-642-29011-4_15

    Chapter  Google Scholar 

  6. Bitansky, N., Vaikuntanathan, V.: A note on perfect correctness by derandomization. In: Coron, J.-S., Nielsen, J.B. (eds.) EUROCRYPT 2017. LNCS, vol. 10211, pp. 592–606. Springer, Cham (2017). https://doi.org/10.1007/978-3-319-56614-6_20

    Chapter  Google Scholar 

  7. Boldyreva, A., Fehr, S., O’Neill, A.: On notions of security for deterministic encryption, and efficient constructions without random oracles. In: Wagner, D. (ed.) CRYPTO 2008. LNCS, vol. 5157, pp. 335–359. Springer, Heidelberg (2008). https://doi.org/10.1007/978-3-540-85174-5_19

    Chapter  Google Scholar 

  8. Boneh, D., Franklin, M.: Identity-based encryption from the weil pairing. In: Kilian, J. (ed.) CRYPTO 2001. LNCS, vol. 2139, pp. 213–229. Springer, Heidelberg (2001). https://doi.org/10.1007/3-540-44647-8_13

    Chapter  Google Scholar 

  9. Boneh, D., et al.: Fully key-homomorphic encryption, arithmetic circuit ABE and compact garbled circuits. In: Nguyen, P.Q., Oswald, E. (eds.) EUROCRYPT 2014. LNCS, vol. 8441, pp. 533–556. Springer, Heidelberg (2014). https://doi.org/10.1007/978-3-642-55220-5_30

    Chapter  Google Scholar 

  10. Boneh, D., Halevi, S., Hamburg, M., Ostrovsky, R.: Circular-secure encryption from decision Diffie-Hellman. In: Wagner, D. (ed.) CRYPTO 2008. LNCS, vol. 5157, pp. 108–125. Springer, Heidelberg (2008). https://doi.org/10.1007/978-3-540-85174-5_7

    Chapter  Google Scholar 

  11. Boneh, D., Sahai, A., Waters, B.: Functional encryption: definitions and challenges. In: Ishai, Y. (ed.) TCC 2011. LNCS, vol. 6597, pp. 253–273. Springer, Heidelberg (2011). https://doi.org/10.1007/978-3-642-19571-6_16

    Chapter  Google Scholar 

  12. Brakerski, Z., Lombardi, A., Segev, G., Vaikuntanathan, V.: Anonymous IBE, leakage resilience and circular security from new assumptions. In: Nielsen, J.B., Rijmen, V. (eds.) EUROCRYPT 2018. LNCS, vol. 10820, pp. 535–564. Springer, Cham (2018). https://doi.org/10.1007/978-3-319-78381-9_20

    Chapter  Google Scholar 

  13. Cho, C., Döttling, N., Garg, S., Gupta, D., Miao, P., Polychroniadou, A.: Laconic oblivious transfer and its applications. In: Katz, J., Shacham, H. (eds.) CRYPTO 2017. LNCS, vol. 10402, pp. 33–65. Springer, Cham (2017). https://doi.org/10.1007/978-3-319-63715-0_2

    Chapter  Google Scholar 

  14. Diffie, W., Hellman, M.E.: New directions in cryptography. IEEE Trans. Inf. Theory 22(6), 644–654 (1976)

    Article  MathSciNet  Google Scholar 

  15. Döttling, N., Garg, S.: From selective IBE to full IBE and selective HIBE. In: Kalai, Y., Reyzin, L. (eds.) TCC 2017. LNCS, vol. 10677, pp. 372–408. Springer, Cham (2017). https://doi.org/10.1007/978-3-319-70500-2_13

    Chapter  Google Scholar 

  16. Döttling, N., Garg, S.: Identity-based encryption from the Diffie-Hellman assumption. In: Katz, J., Shacham, H. (eds.) CRYPTO 2017. LNCS, vol. 10401, pp. 537–569. Springer, Cham (2017). https://doi.org/10.1007/978-3-319-63688-7_18

    Chapter  Google Scholar 

  17. Döttling, N., Garg, S., Hajiabadi, M., Masny, D.: New constructions of identity-based and key-dependent message secure encryption schemes. In: Abdalla, M., Dahab, R. (eds.) PKC 2018. LNCS, vol. 10769, pp. 3–31. Springer, Cham (2018). https://doi.org/10.1007/978-3-319-76578-5_1

    Chapter  MATH  Google Scholar 

  18. Döttling, N., Garg, S., Ishai, Y., Malavolta, G., Mour, T., Ostrovsky, R.: Trapdoor hash functions and their applications. In: Boldyreva, A., Micciancio, D. (eds.) CRYPTO 2019. LNCS, vol. 11694, pp. 3–32. Springer, Cham (2019). https://doi.org/10.1007/978-3-030-26954-8_1

    Chapter  Google Scholar 

  19. Freeman, D.M., Goldreich, O., Kiltz, E., Rosen, A., Segev, G.: More constructions of lossy and correlation-secure trapdoor functions. In: Nguyen, P.Q., Pointcheval, D. (eds.) PKC 2010. LNCS, vol. 6056, pp. 279–295. Springer, Heidelberg (2010). https://doi.org/10.1007/978-3-642-13013-7_17

    Chapter  Google Scholar 

  20. Garg, S., Gay, R., Hajiabadi, M.: New techniques for efficient trapdoor functions and applications. In: Ishai, Y., Rijmen, V. (eds.) EUROCRYPT 2019. LNCS, vol. 11478, pp. 33–63. Springer, Cham (2019). https://doi.org/10.1007/978-3-030-17659-4_2

    Chapter  Google Scholar 

  21. Garg, S., Hajiabadi, M.: Trapdoor functions from the computational Diffie-Hellman assumption. In: Shacham, H., Boldyreva, A. (eds.) CRYPTO 2018. LNCS, vol. 10992, pp. 362–391. Springer, Cham (2018). https://doi.org/10.1007/978-3-319-96881-0_13

    Chapter  Google Scholar 

  22. Gentry, C., Peikert, C., Vaikuntanathan, V.: Trapdoors for hard lattices and new cryptographic constructions. In: Ladner, R.E., Dwork, C. (eds.) 40th ACM STOC, Victoria, BC, Canada, 17–20 May 2008, pp. 197–206. ACM Press (2008)

    Google Scholar 

  23. Gorbunov, S., Vaikuntanathan, V., Wee, H.: Predicate encryption for circuits from LWE. In: Gennaro, R., Robshaw, M. (eds.) CRYPTO 2015. LNCS, vol. 9216, pp. 503–523. Springer, Heidelberg (2015). https://doi.org/10.1007/978-3-662-48000-7_25

    Chapter  Google Scholar 

  24. Goyal, V., Pandey, O., Sahai, A., Waters, B.: Attribute-based encryption for fine-grained access control of encrypted data. In: Juels, A., Wright, R.N., De Capitani di Vimercati, S. (eds.) ACM CCS 2006, Alexandria, Virginia, USA, 30 October–3 November 2006, pp. 89–98. ACM Press (2006). Available as Cryptology ePrint Archive Report 2006/309

    Google Scholar 

  25. Hohenberger, S., Koppula, V., Waters, B.: Chosen ciphertext security from injective trapdoor functions. In: Micciancio, D., Ristenpart, T. (eds.) CRYPTO 2020. LNCS, vol. 12170, pp. 836–866. Springer, Cham (2020). https://doi.org/10.1007/978-3-030-56784-2_28

    Chapter  Google Scholar 

  26. Impagliazzo, R., Levin, L.A., Luby, M.: Pseudo-random generation from one-way functions (extended abstracts). In: 21st ACM STOC, Seattle, WA, USA, 15–17 May 1989, pp. 12–24. ACM Press (1989)

    Google Scholar 

  27. Kiltz, E., Masny, D., Pietrzak, K.: Simple chosen-ciphertext security from low-noise LPN. In: Krawczyk, H. (ed.) PKC 2014. LNCS, vol. 8383, pp. 1–18. Springer, Heidelberg (2014). https://doi.org/10.1007/978-3-642-54631-0_1

    Chapter  Google Scholar 

  28. Kitagawa, F., Matsuda, T., Tanaka, K.: CCA security and trapdoor functions via key-dependent-message security. In: Boldyreva, A., Micciancio, D. (eds.) CRYPTO 2019. LNCS, vol. 11694, pp. 33–64. Springer, Cham (2019). https://doi.org/10.1007/978-3-030-26954-8_2

    Chapter  Google Scholar 

  29. Koppula, V., Waters, B.: Realizing chosen ciphertext security generically in attribute-based encryption and predicate encryption. In: Boldyreva, A., Micciancio, D. (eds.) CRYPTO 2019. LNCS, vol. 11693, pp. 671–700. Springer, Cham (2019). https://doi.org/10.1007/978-3-030-26951-7_23

    Chapter  MATH  Google Scholar 

  30. Lindell, Y., Pinkas, B.: A proof of security of Yao’s protocol for two-party computation. J. Cryptol. 22(2), 161–188 (2009). https://doi.org/10.1007/s00145-008-9036-8

    Article  MathSciNet  MATH  Google Scholar 

  31. Lombardi, A., Quach, W., Rothblum, R.D., Wichs, D., Wu, D.J.: New constructions of reusable designated-verifier NIZKs. In: Boldyreva, A., Micciancio, D. (eds.) CRYPTO 2019. LNCS, vol. 11694, pp. 670–700. Springer, Cham (2019). https://doi.org/10.1007/978-3-030-26954-8_22

    Chapter  Google Scholar 

  32. Peikert, C., Waters, B.: Lossy trapdoor functions and their applications. In: Ladner, R.E., Dwork, C. (eds.) 40th ACM STOC, Victoria, BC, Canada, 17–20 May 2008, pp. 187–196. ACM Press (2008)

    Google Scholar 

  33. Rabin, M.O.: Digital signatures and public key functions as intractable as factorization. Technical report MIT/LCS/TR-212, Massachusetts Institute of Technology, January 1979

    Google Scholar 

  34. Regev, O.: On lattices, learning with errors, random linear codes, and cryptography. In: Gabow, H.N., Fagin, R. (eds.) 37th ACM STOC, Baltimore, MA, USA, 22–24 May 2005, pp. 84–93. ACM Press (2005)

    Google Scholar 

  35. Rivest, R.L., Shamir, A., Adleman, L.M.: A method for obtaining digital signatures and public-key cryptosystems. Commun. Assoc. Comput. Mach. 21(2), 120–126 (1978)

    MathSciNet  MATH  Google Scholar 

  36. Rogaway, P., Shrimpton, T.: A provable-security treatment of the key-wrap problem. In: Vaudenay, S. (ed.) EUROCRYPT 2006. LNCS, vol. 4004, pp. 373–390. Springer, Heidelberg (2006). https://doi.org/10.1007/11761679_23

    Chapter  Google Scholar 

  37. Yao, A.C.-C.: How to generate and exchange secrets (extended abstract). In: 27th FOCS, Toronto, Ontario, Canada, 27–29 October 1986, pp. 162–167. IEEE Computer Society Press (1986)

    Google Scholar 

Download references

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Sanjam Garg .

Editor information

Editors and Affiliations

Rights and permissions

Reprints and permissions

Copyright information

© 2021 International Association for Cryptologic Research

About this paper

Check for updates. Verify currency and authenticity via CrossMark

Cite this paper

Garg, S., Hajiabadi, M., Malavolta, G., Ostrovsky, R. (2021). How to Build a Trapdoor Function from an Encryption Scheme. In: Tibouchi, M., Wang, H. (eds) Advances in Cryptology – ASIACRYPT 2021. ASIACRYPT 2021. Lecture Notes in Computer Science(), vol 13092. Springer, Cham. https://doi.org/10.1007/978-3-030-92078-4_8

Download citation

  • DOI: https://doi.org/10.1007/978-3-030-92078-4_8

  • Published:

  • Publisher Name: Springer, Cham

  • Print ISBN: 978-3-030-92077-7

  • Online ISBN: 978-3-030-92078-4

  • eBook Packages: Computer ScienceComputer Science (R0)

Publish with us

Policies and ethics