Added Encrypt & Decrypt using the ECIES w/ tests

This commit is contained in:
obscuren 2014-12-10 00:03:21 +01:00
parent c24018e273
commit 87adff7e18
2 changed files with 82 additions and 0 deletions

View File

@ -1,14 +1,35 @@
package crypto
import (
"crypto/ecdsa"
"crypto/elliptic"
"crypto/rand"
"crypto/sha256"
"code.google.com/p/go.crypto/ripemd160"
"github.com/ethereum/go-ethereum/ethutil"
"github.com/obscuren/ecies"
"github.com/obscuren/secp256k1-go"
"github.com/obscuren/sha3"
)
func init() {
// specify the params for the s256 curve
ecies.AddParamsForCurve(S256(), ecies.ECIES_AES128_SHA256)
}
func ToECDSA(prv []byte) *ecdsa.PrivateKey {
priv := new(ecdsa.PrivateKey)
priv.PublicKey.Curve = S256()
priv.D = ethutil.BigD(prv)
priv.PublicKey.X, priv.PublicKey.Y = S256().ScalarBaseMult(prv)
return priv
}
func FromECDSA(prv *ecdsa.PrivateKey) []byte {
return prv.D.Bytes()
}
// TODO refactor, remove (bin)
func Sha3(data []byte) []byte {
d := sha3.NewKeccak256()
@ -45,3 +66,24 @@ func Ecrecover(data []byte) []byte {
return r
}
func SigToPub(hash, sig []byte) []byte {
return Ecrecover(append(hash, sig...))
}
func Sign(hash, prv []byte) (sig []byte, err error) {
sig, err = secp256k1.Sign(hash, prv)
return
}
func Encrypt(pub, message []byte) ([]byte, error) {
x, y := elliptic.Unmarshal(S256(), pub)
epub := &ecdsa.PublicKey{S256(), x, y}
return ecies.Encrypt(rand.Reader, ecies.ImportECDSAPublic(epub), message, nil, nil)
}
func Decrypt(prv, ct []byte) ([]byte, error) {
key := ecies.ImportECDSA(ToECDSA(prv))
return key.Decrypt(rand.Reader, ct, nil, nil)
}

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@ -0,0 +1,40 @@
package crypto
import (
"bytes"
"fmt"
"testing"
"github.com/ethereum/go-ethereum/ethutil"
)
func TestBox(t *testing.T) {
prv1 := ethutil.Hex2Bytes("4b50fa71f5c3eeb8fdc452224b2395af2fcc3d125e06c32c82e048c0559db03f")
prv2 := ethutil.Hex2Bytes("d0b043b4c5d657670778242d82d68a29d25d7d711127d17b8e299f156dad361a")
pub2 := ethutil.Hex2Bytes("04bd27a63c91fe3233c5777e6d3d7b39204d398c8f92655947eb5a373d46e1688f022a1632d264725cbc7dc43ee1cfebde42fa0a86d08b55d2acfbb5e9b3b48dc5")
message := []byte("Hello, world.")
ct, err := Encrypt(pub2, message)
if err != nil {
fmt.Println(err.Error())
t.FailNow()
}
pt, err := Decrypt(prv2, ct)
if err != nil {
fmt.Println(err.Error())
t.FailNow()
}
if !bytes.Equal(pt, message) {
fmt.Println("ecies: plaintext doesn't match message")
t.FailNow()
}
_, err = Decrypt(prv1, pt)
if err == nil {
fmt.Println("ecies: encryption should not have succeeded")
t.FailNow()
}
}