Blinded-Key Signatures: securing private keys embedded in mobile agents Extended Abstract Lucas C. Ferreira
Ricardo Dahab
Instituto de Computac¸ao ˜ Universidade Estadual de Campinas - Unicamp Caixa Postal 6176 13083-970, Campinas, SP, Brazil
Instituto de Computac¸ao ˜ Universidade Estadual de Campinas - Unicamp Caixa Postal 6176 13083-970, Campinas, SP, Brazil
[email protected]
[email protected]
ABSTRACT
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Keywords
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1.
INTRODUCTION
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2. DEFINITIONS
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3. BLINDED-KEY SIGNATURES
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3.1 Blinded-key signatures using RSA
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Blinding the key.
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Blinding the key.
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Signing with the blinded key.
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Verifying a blinded-key signature. Signing with the blinded key.
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Verifying a blinded-key signature.
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3.2 Generalized blinded-key signatures
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3.3 Examples for other signature schemes.
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3.4 Security of blinded-key signatures
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4. POLICIES FOR BLINDED-KEY SIGNATURES ) ' " * *&% # " * * $ " # * " % # ( # $ " ' * ^_ "* ^_ ^_ # ' $ # # * ^ _ (
Validity time
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Agency restricting policies
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Number of signatures
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Contents of the agreement
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5.
RELATED WORK
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5.1 Variants of signature schemes
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5.2 Black boxes and mobile agent security
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5.3 Blinded-key signatures and time-limited black-boxes as complementary solutions
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6. EXAMPLE USE FOR BLINDED-KEY SIGNATURES
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6.1 A simplified payment system
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7.
CONCLUSION
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9. BIOGRAPHY # ( '
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