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| author | d0x471b <0x471@protonmail.com> | 2022-12-31 03:45:30 +0300 |
|---|---|---|
| committer | d0x471b <0x471@protonmail.com> | 2022-12-31 03:45:30 +0300 |
| commit | 0f1d7d51de1baa21256fdb7ddafe54aab66172f7 (patch) | |
| tree | 30373f9b64ba6301096f26cdade55ebac4f5e59f /cli/vendor/github.com/btcsuite/btcd/btcec/v2/curve.go | |
| parent | 517ad8d13a6b23328927154226575605be70669f (diff) | |
Diffstat (limited to 'cli/vendor/github.com/btcsuite/btcd/btcec/v2/curve.go')
| -rw-r--r-- | cli/vendor/github.com/btcsuite/btcd/btcec/v2/curve.go | 115 |
1 files changed, 115 insertions, 0 deletions
diff --git a/cli/vendor/github.com/btcsuite/btcd/btcec/v2/curve.go b/cli/vendor/github.com/btcsuite/btcd/btcec/v2/curve.go new file mode 100644 index 0000000..70a9229 --- /dev/null +++ b/cli/vendor/github.com/btcsuite/btcd/btcec/v2/curve.go @@ -0,0 +1,115 @@ +// Copyright (c) 2015-2021 The btcsuite developers +// Copyright (c) 2015-2021 The Decred developers + +package btcec + +import ( + "fmt" + + secp "github.com/decred/dcrd/dcrec/secp256k1/v4" +) + +// JacobianPoint is an element of the group formed by the secp256k1 curve in +// Jacobian projective coordinates and thus represents a point on the curve. +type JacobianPoint = secp.JacobianPoint + +// infinityPoint is the jacobian representation of the point at infinity. +var infinityPoint JacobianPoint + +// MakeJacobianPoint returns a Jacobian point with the provided X, Y, and Z +// coordinates. +func MakeJacobianPoint(x, y, z *FieldVal) JacobianPoint { + return secp.MakeJacobianPoint(x, y, z) +} + +// AddNonConst adds the passed Jacobian points together and stores the result +// in the provided result param in *non-constant* time. +func AddNonConst(p1, p2, result *JacobianPoint) { + secp.AddNonConst(p1, p2, result) +} + +// DecompressY attempts to calculate the Y coordinate for the given X +// coordinate such that the result pair is a point on the secp256k1 curve. It +// adjusts Y based on the desired oddness and returns whether or not it was +// successful since not all X coordinates are valid. +// +// The magnitude of the provided X coordinate field val must be a max of 8 for +// a correct result. The resulting Y field val will have a max magnitude of 2. +func DecompressY(x *FieldVal, odd bool, resultY *FieldVal) bool { + return secp.DecompressY(x, odd, resultY) +} + +// DoubleNonConst doubles the passed Jacobian point and stores the result in +// the provided result parameter in *non-constant* time. +// +// NOTE: The point must be normalized for this function to return the correct +// result. The resulting point will be normalized. +func DoubleNonConst(p, result *JacobianPoint) { + secp.DoubleNonConst(p, result) +} + +// ScalarBaseMultNonConst multiplies k*G where G is the base point of the group +// and k is a big endian integer. The result is stored in Jacobian coordinates +// (x1, y1, z1). +// +// NOTE: The resulting point will be normalized. +func ScalarBaseMultNonConst(k *ModNScalar, result *JacobianPoint) { + secp.ScalarBaseMultNonConst(k, result) +} + +// ScalarMultNonConst multiplies k*P where k is a big endian integer modulo the +// curve order and P is a point in Jacobian projective coordinates and stores +// the result in the provided Jacobian point. +// +// NOTE: The point must be normalized for this function to return the correct +// result. The resulting point will be normalized. +func ScalarMultNonConst(k *ModNScalar, point, result *JacobianPoint) { + secp.ScalarMultNonConst(k, point, result) +} + +// ParseJacobian parses a byte slice point as a secp.Publickey and returns the +// pubkey as a JacobianPoint. If the nonce is a zero slice, the infinityPoint +// is returned. +func ParseJacobian(point []byte) (JacobianPoint, error) { + var result JacobianPoint + + if len(point) != 33 { + str := fmt.Sprintf("invalid nonce: invalid length: %v", + len(point)) + return JacobianPoint{}, makeError(secp.ErrPubKeyInvalidLen, str) + } + + if point[0] == 0x00 { + return infinityPoint, nil + } + + noncePk, err := secp.ParsePubKey(point) + if err != nil { + return JacobianPoint{}, err + } + noncePk.AsJacobian(&result) + + return result, nil +} + +// JacobianToByteSlice converts the passed JacobianPoint to a Pubkey +// and serializes that to a byte slice. If the JacobianPoint is the infinity +// point, a zero slice is returned. +func JacobianToByteSlice(point JacobianPoint) []byte { + if point.X == infinityPoint.X && point.Y == infinityPoint.Y { + return make([]byte, 33) + } + + point.ToAffine() + + return NewPublicKey( + &point.X, &point.Y, + ).SerializeCompressed() +} + +// GeneratorJacobian sets the passed JacobianPoint to the Generator Point. +func GeneratorJacobian(jacobian *JacobianPoint) { + var k ModNScalar + k.SetInt(1) + ScalarBaseMultNonConst(&k, jacobian) +} |
