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[[!meta title="Revocation of the Tails signing key"]]
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This document proposes a mechanism for the distribution and activation of the revocation certificate of the Tails signing key.
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Goals
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Covered by the current proposal:
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- Prevent any single individual from revoking our signing key.
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Allow a coalition of people from the Board to revoke our signing key in case most of the people from the Board become unavailable.
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Allow a coalition of people, not necessarily from the Board, to revoke our signing key in case everybody or almost everybody from the Board becomes unavailable.
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Make it hard for a coalition of people not from the Board to revoke our signing key unless everybody or almost everybody from the Board becomes unavailable.
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People not from the Board shouldn't know how the shares are spread and who has them.
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People in possession of a share of the revocation certificate of the signing key should have instructions on how to use it if needed.
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Groups
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We define four complementary groups of trusted people:
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Group A: people from the Board themselves
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Group B
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Group C
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Group D
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All these people should have an OpenPGP key and understand what a revocation certificate is.
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Cryptographic shares
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We generate a revocation certificate of the signing key and split it into a number of cryptographic shares, using for example Shamir's secret sharing scheme implemented by `gfshare`.
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The following combinations of people could get together and reassemble their shares to reconstruct a complete revocation certificate:
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