56 lines
1.7 KiB
Go
56 lines
1.7 KiB
Go
// Copyright 2010 The Go Authors. All rights reserved.
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// Copyright 2011 ThePiachu. All rights reserved.
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// Copyright 2013-2014 The btcsuite developers
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// Use of this source code is governed by an ISC
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// license that can be found in the LICENSE file.
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package btcec
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// References:
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// [SECG]: Recommended Elliptic Curve Domain Parameters
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// http://www.secg.org/sec2-v2.pdf
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//
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// [GECC]: Guide to Elliptic Curve Cryptography (Hankerson, Menezes, Vanstone)
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// This package operates, internally, on Jacobian coordinates. For a given
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// (x, y) position on the curve, the Jacobian coordinates are (x1, y1, z1)
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// where x = x1/z1² and y = y1/z1³. The greatest speedups come when the whole
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// calculation can be performed within the transform (as in ScalarMult and
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// ScalarBaseMult). But even for Add and Double, it's faster to apply and
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// reverse the transform than to operate in affine coordinates.
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import (
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secp "github.com/decred/dcrd/dcrec/secp256k1/v4"
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)
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// KoblitzCurve provides an implementation for secp256k1 that fits the ECC
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// Curve interface from crypto/elliptic.
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type KoblitzCurve = secp.KoblitzCurve
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// S256 returns a Curve which implements secp256k1.
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func S256() *KoblitzCurve {
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return secp.S256()
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}
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// CurveParams contains the parameters for the secp256k1 curve.
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type CurveParams = secp.CurveParams
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// Params returns the secp256k1 curve parameters for convenience.
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func Params() *CurveParams {
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return secp.Params()
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}
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// Generator returns the public key at the Generator Point.
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func Generator() *PublicKey {
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var (
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result JacobianPoint
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k secp.ModNScalar
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)
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k.SetInt(1)
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ScalarBaseMultNonConst(&k, &result)
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result.ToAffine()
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return NewPublicKey(&result.X, &result.Y)
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}
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