Added concept for cipher setup -- nonworking (hkexchan.gox)

hkexchan.gox

@@ -0,0 +1,75 @@
+/*  Herradura - a Key exchange scheme in the style of Diffie-Hellman Key Exchange.
+    Copyright (C) 2017 Omar Alejandro Herrera Reyna
+
+    This program is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+    golang implementation by Russ Magee (rmagee_at_gmail.com) */
+package herradurakex
+
+import (
+	"crypto/aes"
+	"crypto/cipher"
+	"fmt"
+	"io"
+	"math/big"
+	"os"
+)
+
+const (
+	C_AES_256 = 0
+)
+
+const (
+	H_SHA256 = 0
+)
+
+/*TODO: HMAC derived from HKEx FA.*/
+/* Auxilliary functionality to set up encryption after a channel has
+been negotiated via hkexnet.go -- set up encryption algs with key, IV,
+*/
+func (hd Conn) cryptoSetup(keymat *big.Int, flags uint32, r io.Reader) (ret io.Reader) {
+	// 256 algs should be enough for everybody.(tm)
+	var key []byte
+	var block cipher.Block
+
+	cipherAlg := (flags & 8)
+	//TODO: flags for HMAC from keymat
+	switch cipherAlg {
+	case C_AES_256:
+		key = keymat.Bytes()[0:aes.BlockSize]
+		block, err := aes.NewCipher(key)
+		break
+	default:
+		fmt.Println("DOOFUS SET A VALID CIPHER ALG")
+		block, err := aes.NewCipher(key)
+		os.Exit(1)
+	}
+
+	// If the key is unique for each ciphertext, then it's ok to use a zero
+	// IV.
+	var iv [aes.BlockSize]byte
+	stream := cipher.NewOFB(block, iv[:])
+
+	ret = &cipher.StreamReader{S: stream, R: inFile}
+	// Copy the input file to the output file, decrypting as we go.
+	if _, err := io.Copy(outFile, reader); err != nil {
+		panic(err)
+	}
+
+	// Note that this example is simplistic in that it omits any
+	// authentication of the encrypted data. If you were actually to use
+	// StreamReader in this manner, an attacker could flip arbitrary bits in
+	// the output.
+	return
+}

hkexnet.go

@@ -16,13 +16,9 @@
 package herradurakex
 
 import (
-	"crypto/aes"
-	"crypto/cipher"
 	"fmt"
-	"io"
 	"math/big"
 	"net"
-	"os"
 )
 
 /*---------------------------------------------------------------------*/