cosmos-sdk/crypto/keys/secp256k1/secp256k1_nocgo_test.go

49 lines
1.3 KiB
Go

//go:build !libsecp256k1_sdk
// +build !libsecp256k1_sdk
package secp256k1
import (
"testing"
secp256k1 "github.com/btcsuite/btcd/btcec/v2"
"github.com/stretchr/testify/require"
)
// Ensure that signature verification works, and that
// non-canonical signatures fail.
// Note: run with CGO_ENABLED=0 or go test -tags !cgo.
func TestSignatureVerificationAndRejectUpperS(t *testing.T) {
msg := []byte("We have lingered long enough on the shores of the cosmic ocean.")
for i := 0; i < 500; i++ {
priv := GenPrivKey()
sigStr, err := priv.Sign(msg)
require.NoError(t, err)
var r secp256k1.ModNScalar
r.SetByteSlice(sigStr[:32])
var s secp256k1.ModNScalar
s.SetByteSlice(sigStr[32:64])
require.False(t, s.IsOverHalfOrder())
pub := priv.PubKey()
require.True(t, pub.VerifySignature(msg, sigStr))
// malleate:
var S256 secp256k1.ModNScalar
S256.SetByteSlice(secp256k1.S256().N.Bytes())
s.Negate().Add(&S256)
require.True(t, s.IsOverHalfOrder())
rBytes := r.Bytes()
sBytes := s.Bytes()
malSigStr := make([]byte, 64)
copy(malSigStr[32-len(rBytes):32], rBytes[:])
copy(malSigStr[64-len(sBytes):64], sBytes[:])
require.False(t, pub.VerifySignature(msg, malSigStr),
"VerifyBytes incorrect with malleated & invalid S. sig=%v, key=%v",
malSigStr,
priv,
)
}
}