[#93] Remove golang.org/x/crypto dependency

Signed-off-by: Denis Kirillov <denis@nspcc.ru>

eacl/target.go

@@ -2,8 +2,8 @@ package eacl
 
 import (
 	"crypto/ecdsa"
-	"crypto/elliptic"
 
+	"github.com/nspcc-dev/neo-go/pkg/crypto/keys"
 	v2acl "github.com/nspcc-dev/neofs-api-go/v2/acl"
 )
 
@@ -51,8 +51,7 @@ func SetTargetECDSAKeys(t *Target, pubs ...*ecdsa.PublicKey) {
 	}
 
 	for i := 0; i < ln; i++ {
-		b := elliptic.MarshalCompressed(pubs[i].Curve, pubs[i].X, pubs[i].Y)
-		binKeys = append(binKeys, b)
+		binKeys = append(binKeys, (*keys.PublicKey)(pubs[i]).Bytes())
 	}
 
 	t.SetBinaryKeys(binKeys)
@@ -68,13 +67,9 @@ func TargetECDSAKeys(t *Target) []*ecdsa.PublicKey {
 	pubs := make([]*ecdsa.PublicKey, ln)
 
 	for i := 0; i < ln; i++ {
-		x, y := elliptic.UnmarshalCompressed(elliptic.P256(), binKeys[i])
-		if x != nil && y != nil {
-			pubs[i] = &ecdsa.PublicKey{
-				Curve: elliptic.P256(),
-				X:     x,
-				Y:     y,
-			}
+		p := new(keys.PublicKey)
+		if p.DecodeBytes(binKeys[i]) == nil {
+			pubs[i] = (*ecdsa.PublicKey)(p)
 		}
 	}