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/*
* 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 obfs4
import (
"bytes"
"testing"
"github.com/yawning/obfs4/ntor"
)
func TestHandshakeNtor(t *testing.T) {
// Generate the server node id and id keypair.
nodeID, _ := ntor.NewNodeID([]byte("\x00\x01\x02\x03\x04\x05\x06\x07\x08\x09\x0a\x0b\x0c\x0d\x0e\x0f\x10\x11\x12\x13"))
idKeypair, _ := ntor.NewKeypair(false)
serverFilter, _ := newReplayFilter()
// Test client handshake padding.
for l := clientMinPadLength; l <= clientMaxPadLength; l++ {
// Generate the client state and override the pad length.
clientKeypair, err := ntor.NewKeypair(true)
if err != nil {
t.Fatalf("[%d:0] ntor.NewKeypair failed: %s", l, err)
}
clientHs, err := newClientHandshake(nodeID, idKeypair.Public(), clientKeypair)
if err != nil {
t.Fatalf("[%d:0] newClientHandshake failed: %s", l, err)
}
clientHs.padLen = l
// Generate what the client will send to the server.
clientBlob, err := clientHs.generateHandshake()
if err != nil {
t.Fatalf("[%d:0] clientHandshake.generateHandshake() failed: %s", l, err)
}
if len(clientBlob) > maxHandshakeLength {
t.Fatalf("[%d:0] Generated client body is oversized: %d", l, len(clientBlob))
}
if len(clientBlob) < clientMinHandshakeLength {
t.Fatalf("[%d:0] Generated client body is undersized: %d", l, len(clientBlob))
}
if len(clientBlob) != clientMinHandshakeLength+l {
t.Fatalf("[%d:0] Generated client body incorrect size: %d", l, len(clientBlob))
}
// Generate the server state and override the pad length.
serverHs := newServerHandshake(nodeID, idKeypair)
serverHs.padLen = serverMinPadLength
// Parse the client handshake message.
serverSeed, err := serverHs.parseClientHandshake(serverFilter, clientBlob)
if err != nil {
t.Fatalf("[%d:0] serverHandshake.parseClientHandshake() failed: %s", l, err)
}
// Genrate what the server will send to the client.
serverBlob, err := serverHs.generateHandshake()
if err != nil {
t.Fatal("[%d:0]: serverHandshake.generateHandshake() failed: %s", l, err)
}
// Parse the server handshake message.
clientHs.serverRepresentative = nil
n, clientSeed, err := clientHs.parseServerHandshake(serverBlob)
if err != nil {
t.Fatalf("[%d:0] clientHandshake.parseServerHandshake() failed: %s", l, err)
}
if n != len(serverBlob) {
t.Fatalf("[%d:0] clientHandshake.parseServerHandshake() has bytes remaining: %d", l, n)
}
// Ensure the derived shared secret is the same.
if 0 != bytes.Compare(clientSeed, serverSeed) {
t.Fatalf("[%d:0] client/server seed mismatch", l)
}
}
// Test server handshake padding.
for l := serverMinPadLength; l <= serverMaxPadLength+inlineSeedFrameLength; l++ {
// Generate the client state and override the pad length.
clientKeypair, err := ntor.NewKeypair(true)
if err != nil {
t.Fatalf("[%d:0] ntor.NewKeypair failed: %s", l, err)
}
clientHs, err := newClientHandshake(nodeID, idKeypair.Public(), clientKeypair)
if err != nil {
t.Fatalf("[%d:0] newClientHandshake failed: %s", l, err)
}
clientHs.padLen = clientMinPadLength
// Generate what the client will send to the server.
clientBlob, err := clientHs.generateHandshake()
if err != nil {
t.Fatalf("[%d:1] clientHandshake.generateHandshake() failed: %s", l, err)
}
if len(clientBlob) > maxHandshakeLength {
t.Fatalf("[%d:1] Generated client body is oversized: %d", l, len(clientBlob))
}
// Generate the server state and override the pad length.
serverHs := newServerHandshake(nodeID, idKeypair)
serverHs.padLen = l
// Parse the client handshake message.
serverSeed, err := serverHs.parseClientHandshake(serverFilter, clientBlob)
if err != nil {
t.Fatalf("[%d:1] serverHandshake.parseClientHandshake() failed: %s", l, err)
}
// Genrate what the server will send to the client.
serverBlob, err := serverHs.generateHandshake()
if err != nil {
t.Fatal("[%d:1]: serverHandshake.generateHandshake() failed: %s", l, err)
}
// Parse the server handshake message.
n, clientSeed, err := clientHs.parseServerHandshake(serverBlob)
if err != nil {
t.Fatalf("[%d:1] clientHandshake.parseServerHandshake() failed: %s", l, err)
}
if n != len(serverBlob) {
t.Fatalf("[%d:1] clientHandshake.parseServerHandshake() has bytes remaining: %d", l, n)
}
// Ensure the derived shared secret is the same.
if 0 != bytes.Compare(clientSeed, serverSeed) {
t.Fatalf("[%d:1] client/server seed mismatch", l)
}
}
// Test oversized client padding.
clientKeypair, err := ntor.NewKeypair(true)
if err != nil {
t.Fatalf("ntor.NewKeypair failed: %s", err)
}
clientHs, err := newClientHandshake(nodeID, idKeypair.Public(), clientKeypair)
if err != nil {
t.Fatalf("newClientHandshake failed: %s", err)
}
clientHs.padLen = clientMaxPadLength + 1
clientBlob, err := clientHs.generateHandshake()
if err != nil {
t.Fatalf("clientHandshake.generateHandshake() (forced oversize) failed: %s", err)
}
serverHs := newServerHandshake(nodeID, idKeypair)
_, err = serverHs.parseClientHandshake(serverFilter, clientBlob)
if err == nil {
t.Fatalf("serverHandshake.parseClientHandshake() succeded (oversized)")
}
// Test undersized client padding.
clientHs.padLen = clientMinPadLength - 1
clientBlob, err = clientHs.generateHandshake()
if err != nil {
t.Fatalf("clientHandshake.generateHandshake() (forced undersize) failed: %s", err)
}
serverHs = newServerHandshake(nodeID, idKeypair)
_, err = serverHs.parseClientHandshake(serverFilter, clientBlob)
if err == nil {
t.Fatalf("serverHandshake.parseClientHandshake() succeded (undersized)")
}
// Test oversized server padding.
//
// NB: serverMaxPadLength isn't the real maxPadLength that triggers client
// rejection, because the implementation is written with the asusmption
// that/ the PRNG_SEED is also inlined with the response. Thus the client
// actually accepts longer padding. The server handshake test and this
// test adjust around that.
clientHs.padLen = clientMinPadLength
clientBlob, err = clientHs.generateHandshake()
if err != nil {
t.Fatalf("clientHandshake.generateHandshake() failed: %s", err)
}
serverHs = newServerHandshake(nodeID, idKeypair)
serverHs.padLen = serverMaxPadLength + inlineSeedFrameLength + 1
_, err = serverHs.parseClientHandshake(serverFilter, clientBlob)
if err != nil {
t.Fatalf("serverHandshake.parseClientHandshake() failed: %s", err)
}
serverBlob, err := serverHs.generateHandshake()
if err != nil {
t.Fatal("serverHandshake.generateHandshake() (forced oversize) failed: %s", err)
}
_, _, err = clientHs.parseServerHandshake(serverBlob)
if err == nil {
t.Fatalf("clientHandshake.parseServerHandshake() succeded (oversized)")
}
}
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