go-ethereum/vendor/github.com/btcsuite/btcd/btcec/genprecomps.go

64 lines
1.8 KiB
Go

// Copyright 2015 The btcsuite developers
// Use of this source code is governed by an ISC
// license that can be found in the LICENSE file.
// This file is ignored during the regular build due to the following build tag.
// It is called by go generate and used to automatically generate pre-computed
// tables used to accelerate operations.
// +build ignore
package main
import (
"bytes"
"compress/zlib"
"encoding/base64"
"fmt"
"log"
"os"
"github.com/btcsuite/btcd/btcec"
)
func main() {
fi, err := os.Create("secp256k1.go")
if err != nil {
log.Fatal(err)
}
defer fi.Close()
// Compress the serialized byte points.
serialized := btcec.S256().SerializedBytePoints()
var compressed bytes.Buffer
w := zlib.NewWriter(&compressed)
if _, err := w.Write(serialized); err != nil {
fmt.Println(err)
os.Exit(1)
}
w.Close()
// Encode the compressed byte points with base64.
encoded := make([]byte, base64.StdEncoding.EncodedLen(compressed.Len()))
base64.StdEncoding.Encode(encoded, compressed.Bytes())
fmt.Fprintln(fi, "// Copyright (c) 2015 The btcsuite developers")
fmt.Fprintln(fi, "// Use of this source code is governed by an ISC")
fmt.Fprintln(fi, "// license that can be found in the LICENSE file.")
fmt.Fprintln(fi)
fmt.Fprintln(fi, "package btcec")
fmt.Fprintln(fi)
fmt.Fprintln(fi, "// Auto-generated file (see genprecomps.go)")
fmt.Fprintln(fi, "// DO NOT EDIT")
fmt.Fprintln(fi)
fmt.Fprintf(fi, "var secp256k1BytePoints = %q\n", string(encoded))
a1, b1, a2, b2 := btcec.S256().EndomorphismVectors()
fmt.Println("The following values are the computed linearly " +
"independent vectors needed to make use of the secp256k1 " +
"endomorphism:")
fmt.Printf("a1: %x\n", a1)
fmt.Printf("b1: %x\n", b1)
fmt.Printf("a2: %x\n", a2)
fmt.Printf("b2: %x\n", b2)
}