From bc5ce842a04a0ab226eef0d627e6f9ffb4c2937e Mon Sep 17 00:00:00 2001 From: Andy Wang Date: Sat, 25 Jan 2020 10:19:45 +0000 Subject: [PATCH] Refactor makeAuthenticationPayload to allow easier tests --- internal/client/TLS.go | 5 ++- internal/client/auth.go | 13 ++----- internal/client/auth_test.go | 74 ++++++++++++++++++++++++++++++++++++ internal/client/websocket.go | 3 +- 4 files changed, 84 insertions(+), 11 deletions(-) create mode 100644 internal/client/auth_test.go diff --git a/internal/client/TLS.go b/internal/client/TLS.go index aa2d5bb..2960182 100644 --- a/internal/client/TLS.go +++ b/internal/client/TLS.go @@ -1,6 +1,7 @@ package client import ( + "crypto/rand" "encoding/binary" "github.com/cbeuw/Cloak/internal/util" "net" @@ -45,6 +46,8 @@ func addExtRec(typ []byte, data []byte) []byte { } func unmarshalAuthenticationInfo(ai authenticationPayload, serverName string) (ret clientHelloFields) { + // random is marshalled ephemeral pub key 32 bytes + // The authentication ciphertext and its tag are then distributed among SessionId and X25519KeyShare ret.random = ai.randPubKey[:] ret.sessionId = ai.ciphertextWithTag[0:32] ret.x25519KeyShare = ai.ciphertextWithTag[32:64] @@ -63,7 +66,7 @@ func (DirectTLS) UnitReadFunc() func(net.Conn, []byte) (int, error) { return uti // if the server proceed with Cloak authentication func (DirectTLS) PrepareConnection(sta *State, conn net.Conn) (preparedConn net.Conn, sessionKey []byte, err error) { preparedConn = conn - payload, sharedSecret := makeAuthenticationPayload(sta) + payload, sharedSecret := makeAuthenticationPayload(sta, rand.Reader) chOnly := sta.browser.composeClientHello(unmarshalAuthenticationInfo(payload, sta.ServerName)) chWithRecordLayer := util.AddRecordLayer(chOnly, []byte{0x16}, []byte{0x03, 0x01}) _, err = preparedConn.Write(chWithRecordLayer) diff --git a/internal/client/auth.go b/internal/client/auth.go index 5613cfb..39deb6b 100644 --- a/internal/client/auth.go +++ b/internal/client/auth.go @@ -1,12 +1,10 @@ package client import ( - "crypto/rand" "encoding/binary" - "encoding/hex" "github.com/cbeuw/Cloak/internal/ecdh" "github.com/cbeuw/Cloak/internal/util" - "log" + "io" "sync/atomic" ) @@ -20,9 +18,8 @@ type authenticationPayload struct { } // makeAuthenticationPayload generates the ephemeral key pair, calculates the shared secret, and then compose and -// encrypt the Authentication data. It also composes SNI extension. -func makeAuthenticationPayload(sta *State) (ret authenticationPayload, sharedSecret []byte) { - // random is marshalled ephemeral pub key 32 bytes +// encrypt the authenticationPayload +func makeAuthenticationPayload(sta *State, randReader io.Reader) (ret authenticationPayload, sharedSecret []byte) { /* Authentication data: +----------+----------------+---------------------+-------------+--------------+--------+------------+ @@ -31,8 +28,7 @@ func makeAuthenticationPayload(sta *State) (ret authenticationPayload, sharedSec | 16 bytes | 12 bytes | 1 byte | 8 bytes | 4 bytes | 1 byte | 6 bytes | +----------+----------------+---------------------+-------------+--------------+--------+------------+ */ - // The authentication ciphertext and its tag are then distributed among SessionId and X25519KeyShare - ephPv, ephPub, _ := ecdh.GenerateKey(rand.Reader) + ephPv, ephPub, _ := ecdh.GenerateKey(randReader) copy(ret.randPubKey[:], ecdh.Marshal(ephPub)) plaintext := make([]byte, 48) @@ -48,7 +44,6 @@ func makeAuthenticationPayload(sta *State) (ret authenticationPayload, sharedSec sharedSecret = ecdh.GenerateSharedSecret(ephPv, sta.staticPub) ciphertextWithTag, _ := util.AESGCMEncrypt(ret.randPubKey[:12], sharedSecret, plaintext) - log.Print(hex.EncodeToString(sharedSecret)) copy(ret.ciphertextWithTag[:], ciphertextWithTag[:]) return } diff --git a/internal/client/auth_test.go b/internal/client/auth_test.go new file mode 100644 index 0000000..e6b698d --- /dev/null +++ b/internal/client/auth_test.go @@ -0,0 +1,74 @@ +package client + +import ( + "bytes" + "github.com/cbeuw/Cloak/internal/multiplex" + "io" + "testing" + "time" +) + +func TestMakeAuthenticationPayload(t *testing.T) { + tests := []struct { + state *State + seed io.Reader + expPayload authenticationPayload + expSecret []byte + }{ + { + &State{ + Unordered: false, + SessionID: 3421516597, + UID: []byte{ + 0x4c, 0xd8, 0xcc, 0x15, 0x60, 0x0d, 0x7e, + 0xb6, 0x81, 0x31, 0xfd, 0x80, 0x97, 0x67, 0x37, 0x46}, + staticPub: &[32]byte{ + 0x21, 0x8a, 0x14, 0xce, 0x49, 0x5e, 0xfd, 0x3f, + 0xe4, 0xae, 0x21, 0x3e, 0x51, 0xf7, 0x66, 0xec, + 0x01, 0xd0, 0xb4, 0x87, 0x86, 0x9c, 0x15, 0x9b, + 0x86, 0x19, 0x53, 0x6e, 0x60, 0xe9, 0x51, 0x42}, + Now: func() time.Time { return time.Unix(1579908372, 0) }, + ProxyMethod: "shadowsocks", + EncryptionMethod: multiplex.E_METHOD_PLAIN, + ServerName: "d2jkinvisak5y9.cloudfront.net", + }, + bytes.NewBuffer([]byte{ + 0xf1, 0x1e, 0x42, 0xe1, 0x84, 0x22, 0x07, 0xc5, + 0xc3, 0x5c, 0x0f, 0x7b, 0x01, 0xf3, 0x65, 0x2d, + 0xd7, 0x9b, 0xad, 0xb0, 0xb2, 0x77, 0xa2, 0x06, + 0x6b, 0x78, 0x1b, 0x74, 0x1f, 0x43, 0xc9, 0x80}), + authenticationPayload{ + randPubKey: [32]byte{ + 0xee, 0x9e, 0x41, 0x4e, 0xb3, 0x3b, 0x85, 0x03, + 0x6d, 0x85, 0xba, 0x30, 0x11, 0x31, 0x10, 0x24, + 0x4f, 0x7b, 0xd5, 0x38, 0x50, 0x0f, 0xf2, 0x4d, + 0xa3, 0xdf, 0xba, 0x76, 0x0a, 0xe9, 0x19, 0x19}, + ciphertextWithTag: [64]byte{ + 0x71, 0xb1, 0x6c, 0x5a, 0x60, 0x46, 0x90, 0x12, + 0x36, 0x3b, 0x1b, 0xc4, 0x79, 0x3c, 0xab, 0xdd, + 0x5a, 0x53, 0xc5, 0xed, 0xaf, 0xdb, 0x10, 0x98, + 0x83, 0x96, 0x81, 0xa6, 0xfc, 0xa2, 0x1e, 0xb0, + 0x89, 0xb2, 0x29, 0x71, 0x7e, 0x45, 0x97, 0x54, + 0x11, 0x7d, 0x9b, 0x92, 0xbb, 0xd6, 0xce, 0x37, + 0x3b, 0xb8, 0x8b, 0xfb, 0xb6, 0x40, 0xf0, 0x2c, + 0x6c, 0x55, 0xb9, 0xfc, 0x5d, 0x34, 0x89, 0x41}, + }, + []byte{ + 0xc7, 0xc6, 0x9b, 0xbe, 0xec, 0xf8, 0x35, 0x55, + 0x67, 0x20, 0xcd, 0xeb, 0x74, 0x16, 0xc5, 0x60, + 0xee, 0x9d, 0x63, 0x1a, 0x44, 0xc5, 0x09, 0xf6, + 0xe0, 0x24, 0xad, 0xd2, 0x10, 0xe3, 0x4a, 0x11}, + }, + } + for _, tc := range tests { + func() { + payload, sharedSecret := makeAuthenticationPayload(tc.state, tc.seed) + if payload != tc.expPayload { + t.Errorf("payload doesn't match:\nexp %v\ngot %v", tc.expPayload, payload) + } + if !bytes.Equal(sharedSecret, tc.expSecret) { + t.Errorf("secret doesn't match:\nexp %x\ngot %x", tc.expPayload, payload) + } + }() + } +} diff --git a/internal/client/websocket.go b/internal/client/websocket.go index f15b00b..8269890 100644 --- a/internal/client/websocket.go +++ b/internal/client/websocket.go @@ -1,6 +1,7 @@ package client import ( + "crypto/rand" "encoding/base64" "errors" "fmt" @@ -37,7 +38,7 @@ func (WSOverTLS) PrepareConnection(sta *State, conn net.Conn) (preparedConn net. return preparedConn, nil, fmt.Errorf("failed to parse ws url: %v", err) } - payload, sharedSecret := makeAuthenticationPayload(sta) + payload, sharedSecret := makeAuthenticationPayload(sta, rand.Reader) header := http.Header{} header.Add("hidden", base64.StdEncoding.EncodeToString(append(payload.randPubKey[:], payload.ciphertextWithTag[:]...))) c, _, err := websocket.NewClient(preparedConn, u, header, 16480, 16480)