In Go, P256 is twice as fast as Ed25519

fun_test.go

// chris@cloudtron:~/go/src/fun$ go test -bench .
// goos: linux
// goarch: amd64
// pkg: fun
// BenchmarkSignP256-4                50000             32375 ns/op        
// BenchmarkVerifyP256-4              20000             90285 ns/op
// BenchmarkSignEd25519-4             20000             62050 ns/op
// BenchmarkVerifyEd25519-4           10000            167410 ns/op
package main

import (
	"crypto"
	"crypto/ecdsa"
	"crypto/elliptic"
	"crypto/rand"
	"crypto/sha256"
	"encoding/asn1"
	"math/big"
	"testing"

	"golang.org/x/crypto/ed25519"
)

var msg = []byte("Let's just see how this all works out then why don't we?")

func BenchmarkSignP256(b *testing.B) {
	b.ResetTimer()
	p256 := elliptic.P256()
	sk, _ := ecdsa.GenerateKey(p256, rand.Reader)

	b.ResetTimer()
	for i := 0; i < b.N; i++ {
		h := sha256.New()
		h.Write(msg)
		_, _ = sk.Sign(rand.Reader, h.Sum(nil), crypto.SHA256)
	}
}

type ecdsaSignature struct {
	R, S *big.Int
}

func BenchmarkVerifyP256(b *testing.B) {
	b.ResetTimer()
	p256 := elliptic.P256()
	sk, _ := ecdsa.GenerateKey(p256, rand.Reader)
	pk := sk.Public().(*ecdsa.PublicKey)
	h := sha256.New()
	h.Write(msg)
	der, _ := sk.Sign(rand.Reader, h.Sum(nil), crypto.SHA256)
	sig := new(ecdsaSignature)
	_, err := asn1.Unmarshal(der, sig)
	if err != nil {
		b.Fatal(err)
	}
	h = sha256.New()
	h.Write(msg)
	if !ecdsa.Verify(pk, h.Sum(nil), sig.R, sig.S) {
		b.Fatal("uh oh")
	}

	b.ResetTimer()
	for i := 0; i < b.N; i++ {
		sig = new(ecdsaSignature)
		_, _ = asn1.Unmarshal(der, sig)
		h = sha256.New()
		h.Write(msg)
		_ = ecdsa.Verify(pk, h.Sum(nil), sig.R, sig.S)
	}
}

func BenchmarkSignEd25519(b *testing.B) {
	b.ResetTimer()
	_, sk, _ := ed25519.GenerateKey(rand.Reader)

	b.ResetTimer()
	for i := 0; i < b.N; i++ {
		_, _ = sk.Sign(rand.Reader, msg, crypto.Hash(0))
	}
}

func BenchmarkVerifyEd25519(b *testing.B) {
	b.ResetTimer()
	pk, sk, _ := ed25519.GenerateKey(rand.Reader)
	sig := ed25519.Sign(sk, msg)

	b.ResetTimer()
	for i := 0; i < b.N; i++ {
		_ = ed25519.Verify(pk, msg, sig)
	}
}