mirror of
https://github.com/smallstep/certificates.git
synced 2024-11-05 21:20:34 +00:00
322 lines
8.4 KiB
Go
322 lines
8.4 KiB
Go
// +build cgo
|
|
|
|
package yubikey
|
|
|
|
import (
|
|
"context"
|
|
"crypto"
|
|
"crypto/x509"
|
|
"encoding/hex"
|
|
"net/url"
|
|
"strings"
|
|
|
|
"github.com/go-piv/piv-go/piv"
|
|
"github.com/pkg/errors"
|
|
"github.com/smallstep/certificates/kms/apiv1"
|
|
"github.com/smallstep/certificates/kms/uri"
|
|
)
|
|
|
|
// Scheme is the scheme used in uris.
|
|
const Scheme = "yubikey"
|
|
|
|
// YubiKey implements the KMS interface on a YubiKey.
|
|
type YubiKey struct {
|
|
yk *piv.YubiKey
|
|
pin string
|
|
managementKey [24]byte
|
|
}
|
|
|
|
// New initializes a new YubiKey.
|
|
// TODO(mariano): only one card is currently supported.
|
|
func New(ctx context.Context, opts apiv1.Options) (*YubiKey, error) {
|
|
managementKey := piv.DefaultManagementKey
|
|
|
|
if opts.URI != "" {
|
|
u, err := uri.ParseWithScheme(Scheme, opts.URI)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
if v := u.Pin(); v != "" {
|
|
opts.Pin = v
|
|
}
|
|
if v := u.Get("management-key"); v != "" {
|
|
opts.ManagementKey = v
|
|
}
|
|
}
|
|
|
|
// Deprecated way to set configuration parameters.
|
|
if opts.ManagementKey != "" {
|
|
b, err := hex.DecodeString(opts.ManagementKey)
|
|
if err != nil {
|
|
return nil, errors.Wrap(err, "error decoding managementKey")
|
|
}
|
|
if len(b) != 24 {
|
|
return nil, errors.New("invalid managementKey: length is not 24 bytes")
|
|
}
|
|
copy(managementKey[:], b[:24])
|
|
}
|
|
|
|
cards, err := piv.Cards()
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
if len(cards) == 0 {
|
|
return nil, errors.New("error detecting yubikey: try removing and reconnecting the device")
|
|
}
|
|
|
|
yk, err := piv.Open(cards[0])
|
|
if err != nil {
|
|
return nil, errors.Wrap(err, "error opening yubikey")
|
|
}
|
|
|
|
return &YubiKey{
|
|
yk: yk,
|
|
pin: opts.Pin,
|
|
managementKey: managementKey,
|
|
}, nil
|
|
}
|
|
|
|
func init() {
|
|
apiv1.Register(apiv1.YubiKey, func(ctx context.Context, opts apiv1.Options) (apiv1.KeyManager, error) {
|
|
return New(ctx, opts)
|
|
})
|
|
}
|
|
|
|
// LoadCertificate implements kms.CertificateManager and loads a certificate
|
|
// from the YubiKey.
|
|
func (k *YubiKey) LoadCertificate(req *apiv1.LoadCertificateRequest) (*x509.Certificate, error) {
|
|
slot, err := getSlot(req.Name)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
|
|
cert, err := k.yk.Certificate(slot)
|
|
if err != nil {
|
|
return nil, errors.Wrap(err, "error retrieving certificate")
|
|
}
|
|
|
|
return cert, nil
|
|
}
|
|
|
|
// StoreCertificate implements kms.CertificateManager and stores a certificate
|
|
// in the YubiKey.
|
|
func (k *YubiKey) StoreCertificate(req *apiv1.StoreCertificateRequest) error {
|
|
if req.Certificate == nil {
|
|
return errors.New("storeCertificateRequest 'Certificate' cannot be nil")
|
|
}
|
|
|
|
slot, err := getSlot(req.Name)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
err = k.yk.SetCertificate(k.managementKey, slot, req.Certificate)
|
|
if err != nil {
|
|
return errors.Wrap(err, "error storing certificate")
|
|
}
|
|
|
|
return nil
|
|
}
|
|
|
|
// GetPublicKey returns the public key present in the YubiKey signature slot.
|
|
func (k *YubiKey) GetPublicKey(req *apiv1.GetPublicKeyRequest) (crypto.PublicKey, error) {
|
|
slot, err := getSlot(req.Name)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
|
|
pub, err := k.getPublicKey(slot)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
|
|
return pub, nil
|
|
}
|
|
|
|
// CreateKey generates a new key in the YubiKey and returns the public key.
|
|
func (k *YubiKey) CreateKey(req *apiv1.CreateKeyRequest) (*apiv1.CreateKeyResponse, error) {
|
|
alg, err := getSignatureAlgorithm(req.SignatureAlgorithm, req.Bits)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
slot, name, err := getSlotAndName(req.Name)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
|
|
pub, err := k.yk.GenerateKey(k.managementKey, slot, piv.Key{
|
|
Algorithm: alg,
|
|
PINPolicy: piv.PINPolicyAlways,
|
|
TouchPolicy: piv.TouchPolicyNever,
|
|
})
|
|
if err != nil {
|
|
return nil, errors.Wrap(err, "error generating key")
|
|
}
|
|
return &apiv1.CreateKeyResponse{
|
|
Name: name,
|
|
PublicKey: pub,
|
|
CreateSignerRequest: apiv1.CreateSignerRequest{
|
|
SigningKey: name,
|
|
},
|
|
}, nil
|
|
}
|
|
|
|
// CreateSigner creates a signer using the key present in the YubiKey signature
|
|
// slot.
|
|
func (k *YubiKey) CreateSigner(req *apiv1.CreateSignerRequest) (crypto.Signer, error) {
|
|
slot, err := getSlot(req.SigningKey)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
|
|
pub, err := k.getPublicKey(slot)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
|
|
priv, err := k.yk.PrivateKey(slot, pub, piv.KeyAuth{
|
|
PIN: k.pin,
|
|
PINPolicy: piv.PINPolicyAlways,
|
|
})
|
|
if err != nil {
|
|
return nil, errors.Wrap(err, "error retrieving private key")
|
|
}
|
|
|
|
signer, ok := priv.(crypto.Signer)
|
|
if !ok {
|
|
return nil, errors.New("private key is not a crypto.Signer")
|
|
}
|
|
return signer, nil
|
|
}
|
|
|
|
// Close releases the connection to the YubiKey.
|
|
func (k *YubiKey) Close() error {
|
|
return errors.Wrap(k.yk.Close(), "error closing yubikey")
|
|
}
|
|
|
|
// getPublicKey returns the public key on a slot. First it attempts to do
|
|
// attestation to get a certificate with the public key in it, if this succeeds
|
|
// means that the key was generated in the device. If not we'll try to get the
|
|
// key from a stored certificate in the same slot.
|
|
func (k *YubiKey) getPublicKey(slot piv.Slot) (crypto.PublicKey, error) {
|
|
cert, err := k.yk.Attest(slot)
|
|
if err != nil {
|
|
if cert, err = k.yk.Certificate(slot); err != nil {
|
|
return nil, errors.Wrap(err, "error retrieving public key")
|
|
}
|
|
}
|
|
return cert.PublicKey, nil
|
|
}
|
|
|
|
// signatureAlgorithmMapping is a mapping between the step signature algorithm,
|
|
// and bits for RSA keys, with yubikey ones.
|
|
var signatureAlgorithmMapping = map[apiv1.SignatureAlgorithm]interface{}{
|
|
apiv1.UnspecifiedSignAlgorithm: piv.AlgorithmEC256,
|
|
apiv1.SHA256WithRSA: map[int]piv.Algorithm{
|
|
0: piv.AlgorithmRSA2048,
|
|
1024: piv.AlgorithmRSA1024,
|
|
2048: piv.AlgorithmRSA2048,
|
|
},
|
|
apiv1.SHA512WithRSA: map[int]piv.Algorithm{
|
|
0: piv.AlgorithmRSA2048,
|
|
1024: piv.AlgorithmRSA1024,
|
|
2048: piv.AlgorithmRSA2048,
|
|
},
|
|
apiv1.SHA256WithRSAPSS: map[int]piv.Algorithm{
|
|
0: piv.AlgorithmRSA2048,
|
|
1024: piv.AlgorithmRSA1024,
|
|
2048: piv.AlgorithmRSA2048,
|
|
},
|
|
apiv1.SHA512WithRSAPSS: map[int]piv.Algorithm{
|
|
0: piv.AlgorithmRSA2048,
|
|
1024: piv.AlgorithmRSA1024,
|
|
2048: piv.AlgorithmRSA2048,
|
|
},
|
|
apiv1.ECDSAWithSHA256: piv.AlgorithmEC256,
|
|
apiv1.ECDSAWithSHA384: piv.AlgorithmEC384,
|
|
}
|
|
|
|
func getSignatureAlgorithm(alg apiv1.SignatureAlgorithm, bits int) (piv.Algorithm, error) {
|
|
v, ok := signatureAlgorithmMapping[alg]
|
|
if !ok {
|
|
return 0, errors.Errorf("YubiKey does not support signature algorithm '%s'", alg)
|
|
}
|
|
|
|
switch v := v.(type) {
|
|
case piv.Algorithm:
|
|
return v, nil
|
|
case map[int]piv.Algorithm:
|
|
signatureAlgorithm, ok := v[bits]
|
|
if !ok {
|
|
return 0, errors.Errorf("YubiKey does not support signature algorithm '%s' with '%d' bits", alg, bits)
|
|
}
|
|
return signatureAlgorithm, nil
|
|
default:
|
|
return 0, errors.Errorf("unexpected error: this should not happen")
|
|
}
|
|
}
|
|
|
|
var slotMapping = map[string]piv.Slot{
|
|
"9a": piv.SlotAuthentication,
|
|
"9c": piv.SlotSignature,
|
|
"9e": piv.SlotCardAuthentication,
|
|
"9d": piv.SlotKeyManagement,
|
|
"82": {Key: 0x82, Object: 0x5FC10D},
|
|
"83": {Key: 0x83, Object: 0x5FC10E},
|
|
"84": {Key: 0x84, Object: 0x5FC10F},
|
|
"85": {Key: 0x85, Object: 0x5FC110},
|
|
"86": {Key: 0x86, Object: 0x5FC111},
|
|
"87": {Key: 0x87, Object: 0x5FC112},
|
|
"88": {Key: 0x88, Object: 0x5FC113},
|
|
"89": {Key: 0x89, Object: 0x5FC114},
|
|
"8a": {Key: 0x8a, Object: 0x5FC115},
|
|
"8b": {Key: 0x8b, Object: 0x5FC116},
|
|
"8c": {Key: 0x8c, Object: 0x5FC117},
|
|
"8d": {Key: 0x8d, Object: 0x5FC118},
|
|
"8e": {Key: 0x8e, Object: 0x5FC119},
|
|
"8f": {Key: 0x8f, Object: 0x5FC11A},
|
|
"90": {Key: 0x90, Object: 0x5FC11B},
|
|
"91": {Key: 0x91, Object: 0x5FC11C},
|
|
"92": {Key: 0x92, Object: 0x5FC11D},
|
|
"93": {Key: 0x93, Object: 0x5FC11E},
|
|
"94": {Key: 0x94, Object: 0x5FC11F},
|
|
"95": {Key: 0x95, Object: 0x5FC120},
|
|
}
|
|
|
|
func getSlot(name string) (piv.Slot, error) {
|
|
slot, _, err := getSlotAndName(name)
|
|
return slot, err
|
|
}
|
|
|
|
func getSlotAndName(name string) (piv.Slot, string, error) {
|
|
if name == "" {
|
|
return piv.SlotSignature, "yubikey:slot-id=9c", nil
|
|
}
|
|
|
|
var slotID string
|
|
name = strings.ToLower(name)
|
|
if strings.HasPrefix(name, "yubikey:") {
|
|
u, err := url.Parse(name)
|
|
if err != nil {
|
|
return piv.Slot{}, "", errors.Wrapf(err, "error parsing '%s'", name)
|
|
}
|
|
v, err := url.ParseQuery(u.Opaque)
|
|
if err != nil {
|
|
return piv.Slot{}, "", errors.Wrapf(err, "error parsing '%s'", name)
|
|
}
|
|
if slotID = v.Get("slot-id"); slotID == "" {
|
|
return piv.Slot{}, "", errors.Wrapf(err, "error parsing '%s': slot-id is missing", name)
|
|
}
|
|
} else {
|
|
slotID = name
|
|
}
|
|
|
|
s, ok := slotMapping[slotID]
|
|
if !ok {
|
|
return piv.Slot{}, "", errors.Errorf("unsupported slot-id '%s'", name)
|
|
}
|
|
|
|
name = "yubikey:slot-id=" + url.QueryEscape(slotID)
|
|
return s, name, nil
|
|
}
|