add CashCommandSet

cash_command_set.go

@@ -0,0 +1,70 @@
+package keycard
+
+import (
+	"github.com/status-im/keycard-go/apdu"
+	"github.com/status-im/keycard-go/globalplatform"
+	"github.com/status-im/keycard-go/identifiers"
+	"github.com/status-im/keycard-go/types"
+)
+
+type CashCommandSet struct {
+	c                   types.Channel
+	CashApplicationInfo *types.CashApplicationInfo
+}
+
+func NewCashCommandSet(c types.Channel) *CashCommandSet {
+	return &CashCommandSet{
+		c: c,
+	}
+}
+
+func (cs *CashCommandSet) Select() error {
+	cmd := globalplatform.NewCommandSelect(identifiers.CashInstanceAID)
+	cmd.SetLe(0)
+	resp, err := cs.c.Send(cmd)
+	if err = cs.checkOK(resp, err); err != nil {
+		cs.CashApplicationInfo = &types.CashApplicationInfo{}
+		return err
+	}
+
+	appInfo, err := types.ParseCashApplicationInfo(resp.Data)
+	if err != nil {
+		return err
+	}
+
+	cs.CashApplicationInfo = appInfo
+
+	return nil
+}
+
+func (cs *CashCommandSet) Sign(data []byte) (*types.Signature, error) {
+	cmd, err := NewCommandSign(data, 0x00, "")
+	if err != nil {
+		return nil, err
+	}
+
+	resp, err := cs.c.Send(cmd)
+	if err = cs.checkOK(resp, err); err != nil {
+		return nil, err
+	}
+
+	return types.ParseSignature(data, resp.Data)
+}
+
+func (cs *CashCommandSet) checkOK(resp *apdu.Response, err error, allowedResponses ...uint16) error {
+	if err != nil {
+		return err
+	}
+
+	if len(allowedResponses) == 0 {
+		allowedResponses = []uint16{apdu.SwOK}
+	}
+
+	for _, code := range allowedResponses {
+		if code == resp.Sw {
+			return nil
+		}
+	}
+
+	return apdu.NewErrBadResponse(resp.Sw, "unexpected response")
+}

types/cash_application_info.go

@@ -0,0 +1,38 @@
+package types
+
+import "github.com/status-im/keycard-go/apdu"
+
+type CashApplicationInfo struct {
+	PublicKey     []byte
+	PublicKeyData []byte
+	Version       []byte
+}
+
+func ParseCashApplicationInfo(data []byte) (*CashApplicationInfo, error) {
+	info := &CashApplicationInfo{}
+
+	if data[0] != TagApplicationInfoTemplate {
+		return nil, ErrWrongApplicationInfoTemplate
+	}
+
+	pubKey, err := apdu.FindTag(data, apdu.Tag{TagApplicationInfoTemplate}, apdu.Tag{0x80})
+	if err != nil {
+		return nil, err
+	}
+
+	pubKeyData, err := apdu.FindTag(data, apdu.Tag{TagApplicationInfoTemplate}, apdu.Tag{0x82})
+	if err != nil {
+		return nil, err
+	}
+
+	appVersion, err := apdu.FindTag(data, apdu.Tag{TagApplicationInfoTemplate}, apdu.Tag{0x02})
+	if err != nil {
+		return nil, err
+	}
+
+	info.PublicKey = pubKey
+	info.PublicKeyData = pubKeyData
+	info.Version = appVersion
+
+	return info, nil
+}