1 files changed, 0 insertions, 183 deletions
diff --git a/common/uniformdh/uniformdh.go b/common/uniformdh/uniformdh.go
deleted file mode 100644
index ab94a2e..0000000
--- a/common/uniformdh/uniformdh.go
+++ /dev/null
@@ -1,183 +0,0 @@
-/*
- * Copyright (c) 2014, Yawning Angel <yawning at torproject dot org>
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are met:
- *
- *  * Redistributions of source code must retain the above copyright notice,
- *    this list of conditions and the following disclaimer.
- *
- *  * Redistributions in binary form must reproduce the above copyright notice,
- *    this list of conditions and the following disclaimer in the documentation
- *    and/or other materials provided with the distribution.
- *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
- * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
- * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
- * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
- * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
- * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
- * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
- * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
- * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
- * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
- * POSSIBILITY OF SUCH DAMAGE.
- */
-
-// Package uniformdh implements the Tor Project's UniformDH key exchange
-// mechanism as defined in the obfs3 protocol specification.  This
-// implementation is suitable for obfuscation but MUST NOT BE USED when strong
-// security is required as it is not constant time.
-package uniformdh
-
-import (
-	"fmt"
-	"io"
-	"math/big"
-)
-
-const (
-	// Size is the size of a UniformDH key or shared secret in bytes.
-	Size = 1536 / 8
-
-	// modpStr is the RFC3526 1536-bit MODP Group (Group 5).
-	modpStr = "FFFFFFFFFFFFFFFFC90FDAA22168C234C4C6628B80DC1CD1" +
-		"29024E088A67CC74020BBEA63B139B22514A08798E3404DD" +
-		"EF9519B3CD3A431B302B0A6DF25F14374FE1356D6D51C245" +
-		"E485B576625E7EC6F44C42E9A637ED6B0BFF5CB6F406B7ED" +
-		"EE386BFB5A899FA5AE9F24117C4B1FE649286651ECE45B3D" +
-		"C2007CB8A163BF0598DA48361C55D39A69163FA8FD24CF5F" +
-		"83655D23DCA3AD961C62F356208552BB9ED529077096966D" +
-		"670C354E4ABC9804F1746C08CA237327FFFFFFFFFFFFFFFF"
-
-	g = 2
-)
-
-var modpGroup *big.Int
-var gen *big.Int
-
-// A PrivateKey represents a UniformDH private key.
-type PrivateKey struct {
-	PublicKey
-	privateKey *big.Int
-}
-
-// A PublicKey represents a UniformDH public key.
-type PublicKey struct {
-	bytes     []byte
-	publicKey *big.Int
-}
-
-// Bytes returns the byte representation of a PublicKey.
-func (pub *PublicKey) Bytes() (pubBytes []byte, err error) {
-	if len(pub.bytes) != Size || pub.bytes == nil {
-		return nil, fmt.Errorf("public key is not initialized")
-	}
-	pubBytes = make([]byte, Size)
-	copy(pubBytes, pub.bytes)
-
-	return
-}
-
-// SetBytes sets the PublicKey from a byte slice.
-func (pub *PublicKey) SetBytes(pubBytes []byte) error {
-	if len(pubBytes) != Size {
-		return fmt.Errorf("public key length %d is not %d", len(pubBytes), Size)
-	}
-	pub.bytes = make([]byte, Size)
-	copy(pub.bytes, pubBytes)
-	pub.publicKey = new(big.Int).SetBytes(pub.bytes)
-
-	return nil
-}
-
-// GenerateKey generates a UniformDH keypair using the random source random.
-func GenerateKey(random io.Reader) (priv *PrivateKey, err error) {
-	privBytes := make([]byte, Size)
-	if _, err = io.ReadFull(random, privBytes); err != nil {
-		return
-	}
-	priv, err = generateKey(privBytes)
-
-	return
-}
-
-func generateKey(privBytes []byte) (priv *PrivateKey, err error) {
-	// This function does all of the actual heavy lifting of creating a public
-	// key from a raw 192 byte private key.  It is split so that the KAT tests
-	// can be written easily, and not exposed since non-ephemeral keys are a
-	// terrible idea.
-
-	if len(privBytes) != Size {
-		return nil, fmt.Errorf("invalid private key size %d", len(privBytes))
-	}
-
-	// To pick a private UniformDH key, we pick a random 1536-bit number,
-	// and make it even by setting its low bit to 0
-	privBn := new(big.Int).SetBytes(privBytes)
-	wasEven := privBn.Bit(0) == 0
-	privBn = privBn.SetBit(privBn, 0, 0)
-
-	// Let x be that private key, and X = g^x (mod p).
-	pubBn := new(big.Int).Exp(gen, privBn, modpGroup)
-	pubAlt := new(big.Int).Sub(modpGroup, pubBn)
-
-	// When someone sends her public key to the other party, she randomly
-	// decides whether to send X or p-X.  Use the lowest most bit of the
-	// private key here as the random coin flip since it is masked out and not
-	// used.
-	//
-	// Note: The spec doesn't explicitly specify it, but here we prepend zeros
-	// to the key so that it is always exactly Size bytes.
-	pubBytes := make([]byte, Size)
-	if wasEven {
-		err = prependZeroBytes(pubBytes, pubBn.Bytes())
-	} else {
-		err = prependZeroBytes(pubBytes, pubAlt.Bytes())
-	}
-	if err != nil {
-		return
-	}
-
-	priv = new(PrivateKey)
-	priv.PublicKey.bytes = pubBytes
-	priv.PublicKey.publicKey = pubBn
-	priv.privateKey = privBn
-
-	return
-}
-
-// Handshake generates a shared secret given a PrivateKey and PublicKey.
-func Handshake(privateKey *PrivateKey, publicKey *PublicKey) (sharedSecret []byte, err error) {
-	// When a party wants to calculate the shared secret, she raises the
-	// foreign public key to her private key.
-	secretBn := new(big.Int).Exp(publicKey.publicKey, privateKey.privateKey, modpGroup)
-	sharedSecret = make([]byte, Size)
-	err = prependZeroBytes(sharedSecret, secretBn.Bytes())
-
-	return
-}
-
-func prependZeroBytes(dst, src []byte) error {
-	zeros := len(dst) - len(src)
-	if zeros < 0 {
-		return fmt.Errorf("src length is greater than destination: %d", zeros)
-	}
-	for i := 0; i < zeros; i++ {
-		dst[i] = 0
-	}
-	copy(dst[zeros:], src)
-
-	return nil
-}
-
-func init() {
-	// Load the MODP group and the generator.
-	var ok bool
-	modpGroup, ok = new(big.Int).SetString(modpStr, 16)
-	if !ok {
-		panic("Failed to load the RFC3526 MODP Group")
-	}
-	gen = big.NewInt(g)
-}