90 lines
2.5 KiB
Go
90 lines
2.5 KiB
Go
|
// Package box is an asymmetric implementation of config/secrets using nacl/box
|
||
|
|
package box
|
||
|
|
|
||
|
|
import (
|
||
|
|
"github.com/micro/go-micro/v2/config/secrets"
|
||
|
|
"github.com/pkg/errors"
|
||
|
|
naclbox "golang.org/x/crypto/nacl/box"
|
||
|
|
|
||
|
|
"crypto/rand"
|
||
|
|
)
|
||
|
|
|
||
|
|
const keyLength = 32
|
||
|
|
|
||
|
|
type box struct {
|
||
|
|
options secrets.Options
|
||
|
|
|
||
|
|
publicKey [keyLength]byte
|
||
|
|
privateKey [keyLength]byte
|
||
|
|
}
|
||
|
|
|
||
|
|
// NewCodec returns a nacl-box codec
|
||
|
|
func NewCodec(opts ...secrets.Option) secrets.Codec {
|
||
|
|
b := &box{}
|
||
|
|
for _, o := range opts {
|
||
|
|
o(&b.options)
|
||
|
|
}
|
||
|
|
return b
|
||
|
|
}
|
||
|
|
|
||
|
|
// Init initialises a box
|
||
|
|
func (b *box) Init(opts ...secrets.Option) error {
|
||
|
|
for _, o := range opts {
|
||
|
|
o(&b.options)
|
||
|
|
}
|
||
|
|
if len(b.options.PrivateKey) != keyLength || len(b.options.PublicKey) != keyLength {
|
||
|
|
return errors.Errorf("a public key and a private key of length %d must both be provided", keyLength)
|
||
|
|
}
|
||
|
|
copy(b.privateKey[:], b.options.PrivateKey)
|
||
|
|
copy(b.publicKey[:], b.options.PublicKey)
|
||
|
|
return nil
|
||
|
|
}
|
||
|
|
|
||
|
|
// Options returns options
|
||
|
|
func (b *box) Options() secrets.Options {
|
||
|
|
return b.options
|
||
|
|
}
|
||
|
|
|
||
|
|
// String returns nacl-box
|
||
|
|
func (*box) String() string {
|
||
|
|
return "nacl-box"
|
||
|
|
}
|
||
|
|
|
||
|
|
// Encrypt encrypts a message with the sender's private key and the receipient's public key
|
||
|
|
func (b *box) Encrypt(in []byte, opts ...secrets.EncryptOption) ([]byte, error) {
|
||
|
|
var options secrets.EncryptOptions
|
||
|
|
for _, o := range opts {
|
||
|
|
o(&options)
|
||
|
|
}
|
||
|
|
if len(options.RecipientPublicKey) != keyLength {
|
||
|
|
return []byte{}, errors.New("recepient's public key must be provided")
|
||
|
|
}
|
||
|
|
var recipientPublicKey [keyLength]byte
|
||
|
|
copy(recipientPublicKey[:], options.RecipientPublicKey)
|
||
|
|
var nonce [24]byte
|
||
|
|
if _, err := rand.Reader.Read(nonce[:]); err != nil {
|
||
|
|
return []byte{}, errors.Wrap(err, "couldn't obtain a random nonce from crypto/rand")
|
||
|
|
}
|
||
|
|
return naclbox.Seal(nonce[:], in, &nonce, &recipientPublicKey, &b.privateKey), nil
|
||
|
|
}
|
||
|
|
|
||
|
|
// Decrypt Decrypts a message with the receiver's private key and the sender's public key
|
||
|
|
func (b *box) Decrypt(in []byte, opts ...secrets.DecryptOption) ([]byte, error) {
|
||
|
|
var options secrets.DecryptOptions
|
||
|
|
for _, o := range opts {
|
||
|
|
o(&options)
|
||
|
|
}
|
||
|
|
if len(options.SenderPublicKey) != keyLength {
|
||
|
|
return []byte{}, errors.New("sender's public key bust be provided")
|
||
|
|
}
|
||
|
|
var nonce [24]byte
|
||
|
|
var senderPublicKey [32]byte
|
||
|
|
copy(nonce[:], in[:24])
|
||
|
|
copy(senderPublicKey[:], options.SenderPublicKey)
|
||
|
|
decrypted, ok := naclbox.Open(nil, in[24:], &nonce, &senderPublicKey, &b.privateKey)
|
||
|
|
if !ok {
|
||
|
|
return []byte{}, errors.New("incoming message couldn't be verified / decrypted")
|
||
|
|
}
|
||
|
|
return decrypted, nil
|
||
|
|
}
|