暗号プラットフォーム研究の展望

Nuttapong (Nuts) Attrapadung
CPSEC symposium 2018.12.17

On Cryptography Platform:
Attribute-based Encryption and More

Nuttapong (Nuts) Attrapadung
CPSEC symposium 2018.12.17

About Myself
Nuttapong Attrapadung (Nut/Nuts/Nattsu/ナッツ)
1997-2001
Thailand

Chulalongkorn University
Bachelor Engineering

2001-2007
Japan

University of Tokyo
Master, Ph.D. (Info.Science&Tech)

2007-now
Japan

AIST
researcher

1997
Argentina

International Math Olympiad

2012-2013
FranceÉcole normale supérieure, Paris
visiting researcher
3暗号プラットフォーム研究チームの紹介
他チーム@

共同研究先：三菱電機、
パナソニック、NTT、
日立、KDDI研究所

ナッツ

村上

照屋

須崎

塚本

外部企業・機関設計した汎用的フレームワークの中で、ニーズに沿った応用機能を提供

本研究チーム：暗号技術を応用し、システムの様々なレイヤでセキュアプラットフォーム・フレームワークを設計・開発• JST CREST
研究プロジェクト • Kakenhi• JST ACT-i• 他 (調整中)

権威ある国際学会・ジャーナル
への論文採録による安全性保証

4Big Data
Utilityhealth care, marketing,financial, machine learning …

5

Big Data
Privacy
Problem:traditional encryption
is all-or-nothing
6

Big Data
Q.
Utility + Privacy ?
encryption
with access control
7

Example: Matchmaker Application
profileprofile(handsome ^ rich)_ (aist ^ crypto)<latexit sha1_base64="QD9iyHdLulzl3FodFkMUTg9XI8M=">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</latexit><latexit

aist, crypto<latexit sha1_base64="8TkXZPRElY7xQ5n6QhSDQ3TIp3E=">AAAC2HichVE9b9RAEH0xX+H4yAENEo3FKYjKmjMJcagiaCjzwSURSRTZzuayir9k7510nCLRIWiQaABRgUSB+Bk0/AGKVNSIMkg0FDz7jBDFhbXWOzsz7+2bmSCLdGFEDiesEydPnT4zebZx7vyFi1PNS5dXi7SXh6oTplGarwd+oSKdqI7RJlLrWa78OIjUWrB/r4yv9VVe6DR5YAaZ2or9bqJ3degbujqbjDe2my1xXLk177q2OLPzt2XOo+HNep47Y7cdqVYL9VpMm1+xiR2kCNFDDIUEhnYEHwW/DbQhyOjbwpC+nJau4goHaBDbY5Zihk/vPv9d3jZqb8J7yVlU6JCvRNw5kTam5Yt8kCP5LB/lm/wayzWsOEotA57BCKuy7alnV1d+/hcV8zTY+4s6VrPBLrxKq6b2rPKUVYQjfP/Ry6OVO8vTwxvyTr5T/1s5lE+sIOn/CN8vqeU3x+gpyBVXHRxw74wY+V7ZD5t15XW+Yt54lrDqQU59XVZlcMCB/5mqPd5YdZ22OO2lmdbC3Xr0k7iG67jJ+c5hAfexiA7ZNZ7jFV5bD63H1hPr6SjVmqgxV/DPsl78BmD/o04=</latexit><latexit<latexit sha1_base64="QD9iyHdLulzl3FodFkMUTg9XI8M=">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</latexit><latexit• 2015: infamous leak incident on a matchmakerservice Ashley Madison

http://www.businessinsider.com/cheating-affair-website-ashley-madison-hacked-user-data-leaked-2015-7

This application example is inspired by Hoeteck Wee’s Asiacrypt 2016 talk.

8

Attribute Based Encryption
aist, crypto

M<latexit sha1_base64="u2fF7alAosVaRxNK/vR3FQA1JoA=">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</latexit><latexit(aist ^ crypto)<latexit sha1_base64="QD9iyHdLulzl3FodFkMUTg9XI8M=">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</latexit><latexit

aist, AI

phd, crypto

9Attribute Based Encryption (naively)
aist, crypto

M<latexit sha1_base64="u2fF7alAosVaRxNK/vR3FQA1JoA=">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</latexit><latexit

C<latexit sha1_base64="AjXYTvYyzU3IAZI/NZ6pruxkyEU=">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</latexit>(aist ^ crypto)

Raist Rcrypto

Raist

Rcrypto ) M<latexit sha1_base64="RWonJrPMWdRW+jD5KhoQuzuyCnE=">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</latexit><latexit sha1_base64="l+hzjjB/YoAh0Zo1GjvAl/ZWCoM=">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</latexit><latexit sha1_base64="QD9iyHdLulzl3FodFkMUTg9XI8M=">AAAC2XichVG/T9tQEP5wS5umUAIslVisRiAm6+JCMZ1QuzDyKwEpIGQ7j+DiX7JfIqVRhm6IqVIHBEwgMaD+GSz8AwxMnREjlVgYODuuKobAWc/v3r37vvfdnRW6TiyJrvqUFy/7X73Ovcm/HRh8N1QYHqnEQSOyRdkO3CBas8xYuI4vytKRrlgLI2F6litWrZ2vyf1qU0SxE/grshWKDc+s+86WY5uSQ5V11/Rr+c1CkTSdPs7qukra9OwnmjHYMaYNQ59SSxqlVkRmC0HhD9ZRQwAbDXgQ8CHZd2Ei5q+KEgghxzbQ5ljEnpPeC3SQZ2yDswRnmBzd4X+dT9Us6vM54YxTtM2vuLwiRqoYp0s6o1u6oN90Tfc9udopR6KlxbvVxYpwc2jv/fLdsyiPd4nt/6gnNUtswUi1Oqw9TCNJFXYX3/y+f7v8eWm8PUEndMP6j+mKzrkCv/nXPl0US0dP6ImZy0s72OJV6zLye0k/VK4ryvIF5/VmsdMeRKyvzlVJdHjg/6aq9nYqulYirbQ4VZz7ko0+hzF8wCTPdwZzmMcCysz+DT9xgEOlqvxQdpW9bqrSl2FG8ciUXw9QoaOq</latexit><latexit

C=M<latexit sha1_base64="nXnm0j3Z1ea0AVk8toZCba5FOgw=">AAADCHichVJNa9RQFL2NH6212lE3QjfBocXVcJO2dCwIxW66KbRTpy10ypC8vk5D88XLm6FjyB/oHxBxZcGFuHEnrgTd1B/goivX4rKCGxeeZCIiMvWF5N133j3nnftu3Nj3Es18NmJcunzl6ujYtfHrEzduTlZu3d5Moq4SsikiP1LbrpNI3wtlU3val9uxkk7g+nLLPVzO97d6UiVeFD7W/VjuBk4n9PY94WhA7crs8sNVsxXFfjcxG+20peWRTh2cm2X/wEL1Yx1lWbtS5ZpVn+e5uonggT3LNgJ7wbYQWDUuRpXKsRZVvlCL9igiQV0KSFJIGrFPDiV4dsgiphjYLqXAFCKv2JeU0Ti4XWRJZDhAD/HtYLVToiHWuWZSsAVO8fEqME2a5s/8is/5lF/zV/45VCstNHIvfczugCvj9uTx3Y0f/2UFmDUd/GFd6FnTPtULrx68xwWSVyEG/N6Tp+cbi43pdIZP+Bv8v+Az/ogKwt538XJdNp5f4CeBVlDcYB/v3kAR5+X3YaIuVeZL5A1XEcUdKPjroCpNecN/d9UcHmzaNQu/w/pcdelR2foxmqJ7dB/9XaAlWqE1akL9Gb2nU/pkHBtvjLfGu0GqMVJy7tBfw/jwC572t7o=</latexit>

Raist

Rcryptoaist, AI
Raist RAI
<latexit sha1_base64="vgezhLNNPqfkNH4FBLjFklAN2XE=">AAAC4HichVI9b9RAEH1x+AjhIxdokGhOnIKoTmMTlAtVAg10yYVLIiWnk+1sLlb8hb13ysW6HtEgqkjQECQKxM+g4Q9QpKJGlEGioeDZZ4QoLqy13tnZeW/fzKwT+16qRU4mjMlz5y9cnLo0ffnK1Wszldnr62nUS1zVciM/SjYdO1W+F6qW9rSvNuNE2YHjqw1n/1F+vtFXSepF4VM9iFU7sLuht+u5tqar3exk21od6Gz5yXDYqdSkbjbuy3yjSmPRuicWDWvBMmmYdSlGDeVYiSpfsY0dRHDRQwCFEJq2Dxspvy2YEMT0tZHRl9DyinOFIaaJ7TFKMcKmd5//LndbpTfkPudMC7TLW3zOhMgq5uSLfJBT+Swf5Zv8GsuVFRy5lgFXZ4RVcWfmxc21n/9FBVw19v6iztSssYtGodWj9rjw5Fm4I3z/8Oh07UFzLrsj7+Q79R/LiXxiBmH/h/t+VTXfnKEnJVdQVHDAuTNi5H15ParMKynjFePGs7hFDRLq6zIrjbzhf7paHW+sW3WTz2F1vrb0sGz9FG7hNu6yvwtYwmOsoEX2ZzjCWxwbjvHceGm8GoUaEyXmBv4ZxuvfKD6nGA==</latexit><latexit sha1_base64="RWonJrPMWdRW+jD5KhoQuzuyCnE=">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</latexit>

phd, crypto
Rphd Rcrypto<latexit sha1_base64="h1ccpxgFswC1K9VZcHHqqAJaWlg=">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</latexit><latexit sha1_base64="l+hzjjB/YoAh0Zo1GjvAl/ZWCoM=">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</latexit>

10Attribute Based Encryption (naively)
aist, crypto

M<latexit sha1_base64="u2fF7alAosVaRxNK/vR3FQA1JoA=">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</latexit><latexit

C<latexit sha1_base64="AjXYTvYyzU3IAZI/NZ6pruxkyEU=">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</latexit>(aist ^ crypto)<latexit sha1_base64="QD9iyHdLulzl3FodFkMUTg9XI8M=">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</latexit><latexit

C=M<latexit sha1_base64="nXnm0j3Z1ea0AVk8toZCba5FOgw=">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</latexit>

Raist

RcryptoRaist

Raist Rcrypto

Rcrypto ) M<latexit sha1_base64="RWonJrPMWdRW+jD5KhoQuzuyCnE=">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</latexit><latexit sha1_base64="l+hzjjB/YoAh0Zo1GjvAl/ZWCoM=">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</latexit>😈
aist, AI
Raist RAI
<latexit sha1_base64="vgezhLNNPqfkNH4FBLjFklAN2XE=">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</latexit><latexit sha1_base64="RWonJrPMWdRW+jD5KhoQuzuyCnE=">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</latexit>😈
phd, crypto
Rphd Rcrypto<latexit sha1_base64="h1ccpxgFswC1K9VZcHHqqAJaWlg=">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</latexit>}

mix&match<latexit sha1_base64="l+hzjjB/YoAh0Zo1GjvAl/ZWCoM=">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</latexit>

Not secure if users collude ☹
11

Attribute Based Encryption: Key Idea
Key Idea [SW05]
string 7! function

aist, crypto💧Raist (s) Rcrypto (s)<latexit sha1_base64="hwc8qbOlL4jaDY0f2UZJBow4v/4=">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</latexit><latexit sha1_base64="CWnV7Wrjbtg3wF8+jwYnfArVJ9s=">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</latexit>👿

aist, AI

Raist 7! Raist (s)<latexit sha1_base64="RWonJrPMWdRW+jD5KhoQuzuyCnE=">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</latexit><latexit sha1_base64="hwc8qbOlL4jaDY0f2UZJBow4v/4=">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</latexit>

Raist (t) RAI (t)<latexit sha1_base64="iiaXOObhrPy57LgLFib6y3XsBqg=">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</latexit><latexit sha1_base64="bXWX0GQ1+iLiakWZGjfR9mRaVXs=">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</latexit>💧👿

phd, crypto}

mix&matchfailed!

Rphd (u) Rcrypto (u)<latexit sha1_base64="dsEBGHqCiatEUq7qDmYfnvInI8c=">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</latexit><latexit sha1_base64="umRtbASwpGC4rzWPuQD1ImgAAjU=">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</latexit>

12Attribute Based Encryption: Toy Scheme
aist, crypto

M<latexit sha1_base64="u2fF7alAosVaRxNK/vR3FQA1JoA=">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</latexit><latexit(aist ^ crypto)

C=

{B

M +A
aist

BcryptoAs + Baists + Bcrypto

aist, AIA

t + Baistt + BAI

phd, cryptoAu + Bphdu + Bcrypto

still one-time, private-key scheme ☹
13

Attribute Based Encryption
ABE

Key idea

one-time enc

multiple-time enc

A 7! A(r )private-key enc

public-key enc

The Toy schemeB

B 7! g mod N• Public-key scheme: Anyone can encrypt.
• g B mod N hides B , and hence can be public.

(crypto basic: discrete log is hard.)14

2-input AND

Inner productSubspace
membership

Bounded boolean formulae
Unbounded boolean formulae
Boolean circuits
Arithmetic circuits

ABE for any
policies?

Turing machines15

General Design Framework for ABE
if R(Y, X)=1

M
<latexit sha1_base64="u2fF7alAosVaRxNK/vR3FQA1JoA=">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</latexit><latexitYX

if R(Y, X)=0

Main results:-[Attrapadung EUROCRYPT14][Attrapadung ASIACRYPT16][Attrapadung PKC17]
Independently by [Wee TCC14], [Chen et. al. EUROCRYPT15]

Introduce “Pair encoding” functions f(Y) and g(X)16Big Data
Q.
Utility + Privacy ?
Attribute Based
Encryption
17

Utility + Privacy/Security/Authenticity

Cryptography Platformfunctional encryption
attribute-based encryption
homomorphic signaturehomomorphic encryption
attribute-based signature
secure multi-party computation
pseudo-random functions
secure boot in trusted execution environment

Big Data
Q.
Utility + Privacy ?
when accessing

Attribute Based
Encryption
19

Big Data
Q.
Utility + Privacy ?
when computing
Computing overencrypted data20

Homomorphic Encryption

2 ⇥

5
=

+

3 ⇥

31

7

Our WebAssembly
implementation
Encrypt

0.96 msec

Multiply 24.3 msec

• Application: Secure outsourcing• Fully homomorphic: can do any + , ⇥Decrypt 12.6 msec

@Safari iPhone 7• Leveled homomorphic: limited number of ⇥• Ours: fastest 2-level scheme [Attrapadung et al. AsiaCCS18]

21

Secure Outsourced Computationxx
f “in the box”

f(x)

f(x)

• Hot topic: f for machine learning (training/classification)• example: Microsoft Cryptonet [Dowlin et al. ICML16], …
22

Example: Private Personal Genome Testx
Your chance ofgetting cancer:

y%

f:
y%

cancerprobability
calculation
where f(x)=y• Not practical yet when f is heavy ☹
23

Big Data
Q.
Utility + Privacy ?

..

in joint computing

Secure Multi-Party
Computation Protocol
24Secure Multi-Party Computation (MPC)
Each holds private input<latexit sha1_base64="koJC9Q9XwjMHcOdwYm79mnh5TsQ=">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</latexit><latexit sha1_base64="jcDCoxmhwZIIuBDmGcVJcLMsMlM=">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</latexit>

At the end

x1

x2

…

knows only xi , y

y = f (x1 , . . . , xn )..

<latexit sha1_base64="/3f2MpBVj2W7GyBsLsN/DPpMwJQ=">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</latexit><latexit sha1_base64="+z9L178j89z5KqvGCItcQk5Robg=">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</latexit>(i )<latexit sha1_base64="oA07zW7DNizmQ5PwGJSlgCYueWk=">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</latexit>

interactive protocol<latexit sha1_base64="vQSt99oXUnYv4NQagPzRxQ1oi4U=">AAAC1nichVK/TxRBFP5YFREFTm1MaC5cMFSXtyuGw4poYwkcB5cguewuw7Fhf2V37sJ5wc6QkJhYSWGFiYXxz7DhH6CgsjaWmNhY+O3eGkNxMJvZefPmfd98771xYt9Ltcj5iHHj5q3R22N3xu/em5icKt1/sJ5GncRVDTfyo6Tp2KnyvVA1tKd91YwTZQeOrzacvRfZ+UZXJakXhWu6F6utwG6H3o7n2pqu+n4rbJUqUjVrT2W+VqaxaD0Ri4a1YJk0zKrko4JiLEel73iFbURw0UEAhRCatg8bKb9NmBDE9G2hT19Cy8vPFQ4wTmyHUYoRNr17/Le52yy8IfcZZ5qjXd7icyZEljErZ/JFLuRUvsoP+TOUq59zZFp6XJ0BVsWtqaNH9d/XogKuGrv/UVdq1thBLdfqUXuce7Is3AG++/r4ov5sdbb/WD7JT+o/kXP5xgzC7i/384pa/XiFnpRcQV7BHuf2gJH3ZfUoM6+kiFeMG87i5jVIqK/NrDQO2PB/XS0PN9atqsnnsDJfWXpetH4M05jBHPu7gCW8xDIaZG/jHT7g2Ggab4y3xuEg1BgpMA9xaRjv/wK9+6Kt</latexit>xn• Hot topic: f for machine learning• SecureML [CCS17], MiniONN [CCS17], Gazelle [USENIX18],
Tapas [ICML18], …, Mobius [Our paper, arXiv18]

25

App: Outsource to Non-colluding servers
aid randomness

x2

secret sharing

f(x)

y1

x1

MPC

y2

y1

x2

..

x

x1

f on sharesy2• Our result: Practical protocols via client-aid techniques[Morita, Attrapadung, Teruya, Ohata, Nuida, Hanaoka ESORICS18]

26

Big Data
Q.
Utility + Privacy ?

while authenticating
Attribute Based
Signature27

Attribute Based SignatureX

can sign

X: aist, cryptoY

if R(X, Y)=1

Y: (aist _phd) ^ (crypto_ AI)
Privacy: X is private• Applications: anonymous credentials• Our result: Schemes for any circuits/ Turing machines• [Sakai, Attrapadung, Hanaoka PKC16]• [Sakai, Katsumata, Attrapadung, Hanaoka Asiacrypt18]
28

Big Data
Q.
Util.+ Authenticity?
Homomorphic
Signature29

Homomorphic Signature
a=2 ⇥ b=5 + c=3 ⇥ d=7
Bob

Bob

Bob

Bob

ab+cd=31=

Bob• Application: Verifiable computation• Fully homomorphic: can do any + ,⇥• Linear homomorphic: can do +• Ours: efficient schemes [Attrapadung et al. PKC11, PKC13
ASIACRYPT12]30

What We Do from Now

Utility + Privacy/Security/Authenticity

Cryptography Platformfunctional encryption

attribute-based encryption
homomorphic signaturehomomorphic encryption
attribute-based signature
secure multi-party computation
pseudo-random functions
secure boot in trusted execution environment

What We Do from Now

Utility + Privacy/Security/Authenticity• New applications

Society 5.0

Cryptography Platformfunctional encryption

attribute-based encryption
homomorphic signature•New
primitives/improved
schemeshomomorphic encryption•attribute-based“Cryptographicsignature
Agility”
secure multi-party computation
ability to switch/combine tools
pseudo-random functions
secure boot in trusted execution environment

Summary: I introduced• Cryptography Platform Research Team @• attribute based / homomorphic encryption• attribute based / homomorphic signature..

• secure multi-party computation protocols• Ongoing work
• Cryptographic Agility• Secure and fast implementations
33

Thank you !