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44 lines
1.1 KiB
44 lines
1.1 KiB
8 years ago
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// Copyright 2012 The Go Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style
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// license that can be found in the LICENSE file.
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package bn256
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import (
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"crypto/rand"
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)
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func ExamplePair() {
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// This implements the tripartite Diffie-Hellman algorithm from "A One
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// Round Protocol for Tripartite Diffie-Hellman", A. Joux.
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// http://www.springerlink.com/content/cddc57yyva0hburb/fulltext.pdf
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// Each of three parties, a, b and c, generate a private value.
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a, _ := rand.Int(rand.Reader, Order)
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b, _ := rand.Int(rand.Reader, Order)
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c, _ := rand.Int(rand.Reader, Order)
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// Then each party calculates g₁ and g₂ times their private value.
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pa := new(G1).ScalarBaseMult(a)
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qa := new(G2).ScalarBaseMult(a)
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pb := new(G1).ScalarBaseMult(b)
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qb := new(G2).ScalarBaseMult(b)
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pc := new(G1).ScalarBaseMult(c)
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qc := new(G2).ScalarBaseMult(c)
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// Now each party exchanges its public values with the other two and
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// all parties can calculate the shared key.
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k1 := Pair(pb, qc)
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k1.ScalarMult(k1, a)
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k2 := Pair(pc, qa)
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k2.ScalarMult(k2, b)
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k3 := Pair(pa, qb)
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k3.ScalarMult(k3, c)
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// k1, k2 and k3 will all be equal.
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}
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