mirror of https://github.com/fatedier/frp
53 lines
1003 B
Go
53 lines
1003 B
Go
|
package kcp
|
||
|
|
|
||
|
|
import (
|
||
|
|
"crypto/aes"
|
||
|
|
"crypto/cipher"
|
||
|
|
"crypto/md5"
|
||
|
|
"crypto/rand"
|
||
|
|
"io"
|
||
|
|
)
|
||
|
|
|
||
|
|
// Entropy defines a entropy source
|
||
|
|
type Entropy interface {
|
||
|
|
Init()
|
||
|
|
Fill(nonce []byte)
|
||
|
|
}
|
||
|
|
|
||
|
|
// nonceMD5 nonce generator for packet header
|
||
|
|
type nonceMD5 struct {
|
||
|
|
seed [md5.Size]byte
|
||
|
|
}
|
||
|
|
|
||
|
|
func (n *nonceMD5) Init() { /*nothing required*/ }
|
||
|
|
|
||
|
|
func (n *nonceMD5) Fill(nonce []byte) {
|
||
|
|
if n.seed[0] == 0 { // entropy update
|
||
|
|
io.ReadFull(rand.Reader, n.seed[:])
|
||
|
|
}
|
||
|
|
n.seed = md5.Sum(n.seed[:])
|
||
|
|
copy(nonce, n.seed[:])
|
||
|
|
}
|
||
|
|
|
||
|
|
// nonceAES128 nonce generator for packet headers
|
||
|
|
type nonceAES128 struct {
|
||
|
|
seed [aes.BlockSize]byte
|
||
|
|
block cipher.Block
|
||
|
|
}
|
||
|
|
|
||
|
|
func (n *nonceAES128) Init() {
|
||
|
|
var key [16]byte //aes-128
|
||
|
|
io.ReadFull(rand.Reader, key[:])
|
||
|
|
io.ReadFull(rand.Reader, n.seed[:])
|
||
|
|
block, _ := aes.NewCipher(key[:])
|
||
|
|
n.block = block
|
||
|
|
}
|
||
|
|
|
||
|
|
func (n *nonceAES128) Fill(nonce []byte) {
|
||
|
|
if n.seed[0] == 0 { // entropy update
|
||
|
|
io.ReadFull(rand.Reader, n.seed[:])
|
||
|
|
}
|
||
|
|
n.block.Encrypt(n.seed[:], n.seed[:])
|
||
|
|
copy(nonce, n.seed[:])
|
||
|
|
}
|