func main() {
msg := []byte("This is 18+ chars!")
fmt.Printf("msg == %s\n", msg)
// Encrypt
encBlock, err := aes.NewCipher(PASSPHRASE)
fun.MaybeFatalAt("aes.NewCipher", err)
// See https://github.com/thecloakproject/utils/blob/master/crypt/aes.go
cipher, err := crypt.AESEncryptBytes(encBlock, msg)
fun.MaybeFatalAt("AESEncryptBytes", err)
fmt.Printf("cipher == %v\n", cipher)
// Decrypt
decBlock, err := aes.NewCipher(PASSPHRASE)
fun.MaybeFatalAt("aes.NewCipher", err)
// See https://github.com/thecloakproject/utils/blob/master/crypt/aes.go
plain, err := crypt.AESDecryptBytes(decBlock, cipher)
fun.MaybeFatalAt("AESDecryptBytes", err)
fmt.Printf("plain == %s\n", plain)
msgPadded := utils.PadBytes(msg, decBlock.BlockSize())
// Check for equality
fmt.Printf("\nThey match? %v!\n", bytes.Equal(msgPadded, plain))
// Check for equality in other ways
msgUnpadded := strings.TrimSpace(string(msgPadded))
match := (msgUnpadded == string(plain))
fmt.Printf("\nDo their trimmed versions match? %v!\n", match)
if match {
fmt.Printf("They both equal '%s'\n", msgUnpadded)
}
// Here's how to remove those ugly trailing nulls
fmt.Printf("Cleanest-looking version: '%s'\n",
strings.TrimRight(string(plain), "\x00"))
}
// Continuously read local user input (from telnet) and write it to all remote
// connections
func LocalConnHandler(conn net.Conn) {
// New user connected; add their connection to routing table
connList.AddLocal <- conn
// Close conn and remove it from the routing table when we're done
// here
defer func() {
connList.DeleteLocal <- conn
conn.Close()
}()
// Create new cipher.Block
if DEBUG {
log.Printf("Using shared secret '%s'\n", SharedSecret)
}
encBlock, err := aes.NewCipher([]byte(SharedSecret))
if err != nil {
log.Fatalf("Error creating AES cipher for encryption: %v\n", err)
}
var text []byte
r := bufio.NewReader(conn)
for {
if DEBUG {
log.Printf("Listening for new message...\n")
}
plaintext := []byte{}
isPrefix := true
for isPrefix {
text, isPrefix, err = r.ReadLine()
if DEBUG {
fmt.Printf("isPrefix == %v\n", isPrefix)
}
if err != nil {
if err == io.EOF {
log.Printf("* Disconnected: %s\n", conn.RemoteAddr())
return
}
log.Printf("Error reading message from local conn %s: %v\n",
conn.RemoteAddr(), err)
break
}
if DEBUG {
fmt.Printf("text == %s\n", text)
}
plaintext = append(plaintext, text...)
}
// Print user input to screen
now := time.Now().Format(time.Kitchen)
fmt.Printf("[%s] %s: %s\n", now, conn.RemoteAddr(), plaintext)
// Encrypt plaintext coming from local user over telnet
ciphertext, err := crypt.AESEncryptBytes(encBlock, plaintext)
if err != nil {
log.Printf("Error encrypting '%s': %v\n", plaintext, err)
continue
}
// Asynchronously write encrypted message to all remote
// connections
go func() {
connList.WriteToRemotes <- &types.Cipherstore{conn, ciphertext}
}()
}
}