From 339c63f0c8cd4374f6fa26484498eb6fa91b7bca Mon Sep 17 00:00:00 2001 From: Yawning Angel Date: Sun, 17 Aug 2014 17:11:03 +0000 Subject: Massive cleanup/code reorg. * Changed obfs4proxy to be more like obfsproxy in terms of design, including being an easy framework for developing new TCP/IP style pluggable transports. * Added support for also acting as an obfs2/obfs3 client or bridge as a transition measure (and because the code itself is trivial). * Massively cleaned up the obfs4 and related code to be easier to read, and more idiomatic Go-like in style. * To ease deployment, obfs4proxy will now autogenerate the node-id, curve25519 keypair, and drbg seed if none are specified, and save them to a JSON file in the pt_state directory (Fixes Tor bug #12605). --- transports/obfs4/handshake_ntor_test.go | 222 ++++++++++++++++++++++++++++++++ 1 file changed, 222 insertions(+) create mode 100644 transports/obfs4/handshake_ntor_test.go (limited to 'transports/obfs4/handshake_ntor_test.go') diff --git a/transports/obfs4/handshake_ntor_test.go b/transports/obfs4/handshake_ntor_test.go new file mode 100644 index 0000000..fa03420 --- /dev/null +++ b/transports/obfs4/handshake_ntor_test.go @@ -0,0 +1,222 @@ +/* + * Copyright (c) 2014, Yawning Angel + * 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" + + "git.torproject.org/pluggable-transports/obfs4.git/common/ntor" + "git.torproject.org/pluggable-transports/obfs4.git/common/replayfilter" +) + +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, _ := replayfilter.New(replayTTL) + + // 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 := newClientHandshake(nodeID, idKeypair.Public(), clientKeypair) + 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. + serverKeypair, err := ntor.NewKeypair(true) + if err != nil { + t.Fatalf("[%d:0] ntor.NewKeypair failed: %s", l, err) + } + serverHs := newServerHandshake(nodeID, idKeypair, serverKeypair) + 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 := newClientHandshake(nodeID, idKeypair.Public(), clientKeypair) + 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. + serverKeypair, err := ntor.NewKeypair(true) + if err != nil { + t.Fatalf("[%d:0] ntor.NewKeypair failed: %s", l, err) + } + serverHs := newServerHandshake(nodeID, idKeypair, serverKeypair) + 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 := 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) + } + serverKeypair, err := ntor.NewKeypair(true) + if err != nil { + t.Fatalf("ntor.NewKeypair failed: %s", err) + } + serverHs := newServerHandshake(nodeID, idKeypair, serverKeypair) + _, 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, serverKeypair) + _, 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, serverKeypair) + 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)") + } +} -- cgit v1.2.3