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# Verifiable Secret Sharing for Shamir Threshold Scheme
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# Verifiable Secret Sharing for Shamir Threshold Scheme
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-This is an implementation of Shamir threshold scheme with the ability for
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-participants to to verify and update shares.
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+This implementation was part of the contribution for the following paper:
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+
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+Bailey Kacsmar, Chelsea Komlo, Florian Kerschbaum, Ian Goldberg.
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+"Mind the Gap: Ceremonies for Applied Secret Sharing."
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+Proceedings on Privacy Enhancing Technologies. Vol. 2020, No. 2. 18
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+pages. April 2020.
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+
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+This library presents a subset of the presented improvements to Shamir's
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+threshold scheme presented in this paper. As such, this library provides the
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+ability for participants to verify the integrity of shares received by a central dealer,
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+and for participants to update shares in the future, providing protection
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+against an adversary who can collect a threshold number of shares across
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+update epochs, but not within a single epoch.
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+
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+## Use
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+
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+Note that this library does not provide support for serialization and
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+deserialization of shares in order to securely transmit and store shares after
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+they have been generated. Furthermore, the caller of ```generate_shares``` will
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+need to account for securely deleting shares once they have been properly
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+transmitted to participants.
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+
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+Furthermore, this library does not account for how participants should handle
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+the case when a share or update is not valid.
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+
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+## Additional Improvements
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+
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+Note that although the paper discusses additional improvements to Shamir's
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+Threshold Scheme, we did not include all improvements in this library due the
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+variance in implrementation requirements. For examle, when operating in
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+Extended Mode, the integrity value can be distributed along with shares in
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+order to allow for validating the secret document upon recovery. However, as
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+platform and security requirements can change how documents are encrypted, we
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+opted to not include improvements for the Extended mode of operation in this
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+library; see the paper (Figure 5 specifically) for more details.
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+
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Chelsea H. Komlo