Documentation
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Overview ¶
Package share implements Shamir secret sharing and polynomial commitments. Shamir's scheme allows to split a secret value into multiple parts, so called shares, by evaluating a secret sharing polynomial at certain indices. The shared secret can only be reconstructed (via Lagrange interpolation) if a threshold of the participants provide their shares. A polynomial commitment scheme allows a committer to commit to a secret sharing polynomial so that a verifier can check the claimed evaluations of the committed polynomial. Both schemes of this package are core building blocks for more advanced secret sharing techniques.
Index ¶
- func RecoverCommit(g abstract.Group, shares []*PubShare, t, n int) (abstract.Point, error)
- func RecoverSecret(g abstract.Group, shares []*PriShare, t, n int) (abstract.Scalar, error)
- type PriPoly
- func (p *PriPoly) Add(q *PriPoly) (*PriPoly, error)
- func (p *PriPoly) Commit(b abstract.Point) *PubPoly
- func (p *PriPoly) Equal(q *PriPoly) bool
- func (p *PriPoly) Eval(i int) *PriShare
- func (p *PriPoly) Mul(q *PriPoly) *PriPoly
- func (p *PriPoly) Secret() abstract.Scalar
- func (p *PriPoly) Shares(n int) []*PriShare
- func (p *PriPoly) String() string
- func (p *PriPoly) Threshold() int
- type PriShare
- type PubPoly
- func (p *PubPoly) Add(q *PubPoly) (*PubPoly, error)
- func (p *PubPoly) Check(s *PriShare) bool
- func (p *PubPoly) Commit() abstract.Point
- func (p *PubPoly) Equal(q *PubPoly) bool
- func (p *PubPoly) Eval(i int) *PubShare
- func (p *PubPoly) Info() (abstract.Point, []abstract.Point)
- func (p *PubPoly) Shares(n int) []*PubShare
- func (p *PubPoly) Threshold() int
- type PubShare
Constants ¶
This section is empty.
Variables ¶
This section is empty.
Functions ¶
func RecoverCommit ¶
RecoverCommit reconstructs the secret commitment p(0) from a list of public shares using Lagrange interpolation.
Types ¶
type PriPoly ¶
type PriPoly struct {
// contains filtered or unexported fields
}
PriPoly represents a secret sharing polynomial.
func NewPriPoly ¶
NewPriPoly creates a new secret sharing polynomial for the cryptographic group g, the secret sharing threshold t, and the secret to be shared s.
func RecoverPriPoly ¶
RecoverPriPoly takes a list of shares and the parameters t and n to reconstruct the secret polynomial completely, i.e., all private coefficients. It is up to the caller to make sure there are enough shares to correctly re-construct the polynomial. There must be at least t shares.
func (*PriPoly) Add ¶
Add computes the component-wise sum of the polynomials p and q and returns it as a new polynomial.
func (*PriPoly) Commit ¶
Commit creates a public commitment polynomial for the given base point b or the standard base if b == nil.
func (*PriPoly) Mul ¶
Mul multiples p and q together. The result is a polynomial of the sum of the two degrees of p and q. NOTE: it does not check for null coefficients after the multiplication, so the degree of the polynomial is "always" as described above. This is only to use in secret sharing schemes, and is not to be considered a general polynomial manipulation routine.
func (*PriPoly) Secret ¶
GetSecret returns the shared secret p(0), i.e., the constant term of the polynomial.
type PubPoly ¶
type PubPoly struct {
// contains filtered or unexported fields
}
PubPoly represents a public commitment polynomial to a secret sharing polynomial.
func NewPubPoly ¶
NewPubPoly creates a new public commitment polynomial.
func (*PubPoly) Add ¶
Add computes the component-wise sum of the polynomials p and q and returns it as a new polynomial. NOTE: If the base points p.b and q.b are different then the base point of the resulting PubPoly cannot be computed without knowing the discrete logarithm between p.b and q.b. In this particular case, we are using p.b as a default value which of course does not correspond to the correct base point and thus should not be used in further computations.
func (*PubPoly) Commit ¶
Commit returns the secret commitment p(0), i.e., the constant term of the polynomial.
func (*PubPoly) Info ¶
Info returns the base point and the commitments to the polynomial coefficients.
Source Files
Directories
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| Path | Synopsis |
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Package dkg implements the protocol described in "Secure Distributed Key Generation for Discrete-Log Based Cryptosystems" by R. Gennaro, S. Jarecki, H. Krawczyk, and T. Rabin.
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Package dkg implements the protocol described in "Secure Distributed Key Generation for Discrete-Log Based Cryptosystems" by R. Gennaro, S. Jarecki, H. Krawczyk, and T. Rabin. |
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DSS implements the Distributed Schnorr Signature protocol from the paper "Provably Secure Distributed Schnorr Signatures and a (t, n) Threshold Scheme for Implicit Certificates".
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DSS implements the Distributed Schnorr Signature protocol from the paper "Provably Secure Distributed Schnorr Signatures and a (t, n) Threshold Scheme for Implicit Certificates". |
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Package pvss implements public verifiable secret sharing as introduced in "A Simple Publicly Verifiable Secret Sharing Scheme and its Application to Electronic Voting" by Berry Schoenmakers.
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Package pvss implements public verifiable secret sharing as introduced in "A Simple Publicly Verifiable Secret Sharing Scheme and its Application to Electronic Voting" by Berry Schoenmakers. |
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Package vss implements the verifiable secret sharing scheme from the paper "Provably Secure Distributed Schnorr Signatures and a (t, n) Threshold Scheme for Implicit Certificates".
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Package vss implements the verifiable secret sharing scheme from the paper "Provably Secure Distributed Schnorr Signatures and a (t, n) Threshold Scheme for Implicit Certificates". |