Merge pull request #27 from ecies/cgo-support

CGO secp256k1 support added, more mature version of Go native version…

.github/workflows/go.yml

@@ -18,17 +18,29 @@ jobs:
       with:
         go-version: 1.17
 
-    - name: Build
+    - name: Build w/ CGO
       run: GOOS=linux go build
 
+    - name: Build w/o CGO
+      run: GOOS=linux CGO_ENABLED=0 go build
+
     - name: WASM Build
       run: GOOS=js GOARCH=wasm go build
 
-    - name: Test decompression
+    - name: Test decompression w/ CGO
       run: go test -v -run TestPublicKeyDecompression -count 100
 
-    - name: Test
+    - name: Test decompression w/o CGO
+      run: CGO_ENABLED=0 go test -v -run TestPublicKeyDecompression -count 100
+
+    - name: Test w/ CGO
       run: go test -v ./...
 
-    - name: Test race
+    - name: Test w/o CGO
+      run: CGO_ENABLED=0 go test -v ./...
+
+    - name: Test race w/ CGO
       run: go test -race -v ./...
+
+    - name: Test race w/o CGO
+      run: go test -tags=ecies_test_race -race -v ./...

ecies.go

@@ -7,8 +7,6 @@ import (
 	"crypto/rand"
 	"fmt"
 	"math/big"
-
-	"github.com/fomichev/secp256k1"
 )
 
 // Encrypt encrypts a passed message with a receiver public key, returns ciphertext or encryption error
@@ -66,7 +64,7 @@ func Decrypt(privkey *PrivateKey, msg []byte) ([]byte, error) {
 
 	// Ephemeral sender public key
 	ethPubkey := &PublicKey{
-		Curve: secp256k1.SECP256K1(),
+		Curve: getCurve(),
 		X:     new(big.Int).SetBytes(msg[1:33]),
 		Y:     new(big.Int).SetBytes(msg[33:65]),
 	}

go.mod

@@ -1,12 +1,10 @@
 module github.com/ecies/go/v2
 
 require (
-	github.com/davecgh/go-spew v1.1.1 // indirect
-	github.com/fomichev/secp256k1 v0.0.0-20180413221153-00116ff8c62f
-	github.com/kr/pretty v0.1.0 // indirect
+	github.com/decred/dcrd/dcrec/secp256k1/v4 v4.0.1
+	github.com/ethereum/go-ethereum v1.10.15
 	github.com/stretchr/testify v1.7.0
 	golang.org/x/crypto v0.0.0-20220131195533-30dcbda58838
-	gopkg.in/check.v1 v1.0.0-20180628173108-788fd7840127 // indirect
 )
 
 go 1.13

privatekey.go

@@ -8,8 +8,6 @@ import (
 	"encoding/hex"
 	"fmt"
 	"math/big"
-
-	"github.com/fomichev/secp256k1"
 )
 
 // PrivateKey is an instance of secp256k1 private key with nested public key
@@ -20,7 +18,7 @@ type PrivateKey struct {
 
 // GenerateKey generates secp256k1 key pair
 func GenerateKey() (*PrivateKey, error) {
-	curve := secp256k1.SECP256K1()
+	curve := getCurve()
 
 	p, x, y, err := elliptic.GenerateKey(curve, rand.Reader)
 	if err != nil {
@@ -49,7 +47,7 @@ func NewPrivateKeyFromHex(s string) (*PrivateKey, error) {
 
 // NewPrivateKeyFromBytes decodes private key raw bytes, computes public key and returns PrivateKey instance
 func NewPrivateKeyFromBytes(priv []byte) *PrivateKey {
-	curve := secp256k1.SECP256K1()
+	curve := getCurve()
 	x, y := curve.ScalarBaseMult(priv)
 
 	return &PrivateKey{

publickey.go

@@ -7,8 +7,6 @@ import (
 	"encoding/hex"
 	"fmt"
 	"math/big"
-
-	"github.com/fomichev/secp256k1"
 )
 
 // PublicKey instance with nested elliptic.Curve interface (secp256k1 instance in our case)
@@ -30,7 +28,7 @@ func NewPublicKeyFromHex(s string) (*PublicKey, error) {
 // NewPublicKeyFromBytes decodes public key raw bytes and returns PublicKey instance;
 // Supports both compressed and uncompressed public keys
 func NewPublicKeyFromBytes(b []byte) (*PublicKey, error) {
-	curve := secp256k1.SECP256K1()
+	curve := getCurve()
 
 	switch b[0] {
 	case 0x02, 0x03:

secp256k1_cgo.go

@@ -0,0 +1,14 @@
+//go:build cgo && !ecies_test_race
+// +build cgo,!ecies_test_race
+
+package eciesgo
+
+import (
+	"crypto/elliptic"
+
+	"github.com/ethereum/go-ethereum/crypto/secp256k1"
+)
+
+func getCurve() elliptic.Curve {
+	return secp256k1.S256()
+}

secp256k1_nocgo.go

@@ -0,0 +1,14 @@
+//go:build !cgo || ecies_test_race
+// +build !cgo ecies_test_race
+
+package eciesgo
+
+import (
+	"crypto/elliptic"
+
+	"github.com/decred/dcrd/dcrec/secp256k1/v4"
+)
+
+func getCurve() elliptic.Curve {
+	return secp256k1.S256()
+}