@ -19,17 +19,13 @@ package madmin
import (
"bytes"
"crypto/aes"
"crypto/cipher"
"crypto/rand"
"errors"
"io"
"io/ioutil"
"github.com/secure-io/sio-go"
"github.com/secure-io/sio-go/sioutil"
"golang.org/x/crypto/argon2"
"golang.org/x/crypto/chacha20poly1305"
"golang.org/x/sys/cpu"
)
// EncryptData encrypts the data with an unique key
@ -39,26 +35,27 @@ import (
// salt | AEAD ID | nonce | encrypted data
// 32 1 8 ~ len(data)
func EncryptData ( password string , data [ ] byte ) ( [ ] byte , error ) {
salt := make ( [ ] byte , 32 )
if _ , err := io . ReadFull ( rand . Reader , salt ) ; err != nil {
return nil , err
}
salt := sioutil . MustRandom ( 32 )
// Derive an unique 256 bit key from the password and the random salt.
key := argon2 . IDKey ( [ ] byte ( password ) , salt , 1 , 64 * 1024 , 4 , 32 )
// Create a new AEAD instance - either AES-GCM if the CPU provides
// an AES hardware implementation or ChaCha20-Poly1305 otherwise.
id , cipher , err := newAEAD ( key )
if err != nil {
return nil , err
var (
id byte
err error
stream * sio . Stream
)
if sioutil . NativeAES ( ) { // Only use AES-GCM if we can use an optimized implementation
id = aesGcm
stream , err = sio . AES_256_GCM . Stream ( key )
} else {
id = c20p1305
stream , err = sio . ChaCha20Poly1305 . Stream ( key )
}
stream := sio . NewStream ( cipher , sio . BufSize )
nonce := make ( [ ] byte , stream . NonceSize ( ) )
if _ , err := io . ReadFull ( rand . Reader , nonce ) ; err != nil {
if err != nil {
return nil , err
}
nonce := sioutil . MustRandom ( stream . NonceSize ( ) )
// ciphertext = salt || AEAD ID | nonce | encrypted data
cLen := int64 ( len ( salt ) + 1 + len ( nonce ) + len ( data ) ) + stream . Overhead ( int64 ( len ( data ) ) )
@ -104,11 +101,21 @@ func DecryptData(password string, data io.Reader) ([]byte, error) {
}
key := argon2 . IDKey ( [ ] byte ( password ) , salt [ : ] , 1 , 64 * 1024 , 4 , 32 )
cipher , err := parseAEAD ( id [ 0 ] , key )
var (
err error
stream * sio . Stream
)
switch id [ 0 ] {
case aesGcm :
stream , err = sio . AES_256_GCM . Stream ( key )
case c20p1305 :
stream , err = sio . ChaCha20Poly1305 . Stream ( key )
default :
err = errors . New ( "madmin: invalid AEAD algorithm ID" )
}
if err != nil {
return nil , err
}
stream := sio . NewStream ( cipher , sio . BufSize )
return ioutil . ReadAll ( stream . DecryptReader ( data , nonce [ : ] , nil ) )
}
@ -116,40 +123,3 @@ const (
aesGcm = 0x00
c20p1305 = 0x01
)
// newAEAD creates a new AEAD instance from the given key.
// If the CPU provides an AES hardware implementation it
// returns an AES-GCM instance. Otherwise it returns a
// ChaCha20-Poly1305 instance.
//
// newAEAD also returns a byte as algorithm ID indicating
// which AEAD scheme it has selected.
func newAEAD ( key [ ] byte ) ( byte , cipher . AEAD , error ) {
if ( cpu . X86 . HasAES && cpu . X86 . HasPCLMULQDQ ) || cpu . S390X . HasAES || cpu . PPC64 . IsPOWER8 || cpu . ARM64 . HasAES {
block , err := aes . NewCipher ( key )
if err != nil {
return 0 , nil , err
}
c , err := cipher . NewGCM ( block )
return aesGcm , c , err
}
c , err := chacha20poly1305 . New ( key )
return c20p1305 , c , err
}
// parseAEAD creates a new AEAD instance from the id and key.
// The id must be either 0 (AES-GCM) or 1 (ChaCha20-Poly1305).
func parseAEAD ( id byte , key [ ] byte ) ( cipher . AEAD , error ) {
switch id {
case aesGcm :
block , err := aes . NewCipher ( key )
if err != nil {
return nil , err
}
return cipher . NewGCM ( block )
case c20p1305 :
return chacha20poly1305 . New ( key )
default :
return nil , errors . New ( "madmin: invalid AEAD algorithm ID" )
}
}
Andreas Auernhammer
5 years ago
committed by