1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
5 #include "net/socket/socks_client_socket.h"
7 #include "base/basictypes.h"
9 #include "base/callback_helpers.h"
10 #include "base/compiler_specific.h"
11 #include "base/sys_byteorder.h"
12 #include "net/base/io_buffer.h"
13 #include "net/base/net_log.h"
14 #include "net/base/net_util.h"
15 #include "net/socket/client_socket_handle.h"
19 // Every SOCKS server requests a user-id from the client. It is optional
20 // and we send an empty string.
21 static const char kEmptyUserId[] = "";
23 // For SOCKS4, the client sends 8 bytes plus the size of the user-id.
24 static const unsigned int kWriteHeaderSize = 8;
26 // For SOCKS4 the server sends 8 bytes for acknowledgement.
27 static const unsigned int kReadHeaderSize = 8;
29 // Server Response codes for SOCKS.
30 static const uint8 kServerResponseOk = 0x5A;
31 static const uint8 kServerResponseRejected = 0x5B;
32 static const uint8 kServerResponseNotReachable = 0x5C;
33 static const uint8 kServerResponseMismatchedUserId = 0x5D;
35 static const uint8 kSOCKSVersion4 = 0x04;
36 static const uint8 kSOCKSStreamRequest = 0x01;
38 // A struct holding the essential details of the SOCKS4 Server Request.
39 // The port in the header is stored in network byte order.
40 struct SOCKS4ServerRequest {
46 COMPILE_ASSERT(sizeof(SOCKS4ServerRequest) == kWriteHeaderSize,
47 socks4_server_request_struct_wrong_size);
49 // A struct holding details of the SOCKS4 Server Response.
50 struct SOCKS4ServerResponse {
56 COMPILE_ASSERT(sizeof(SOCKS4ServerResponse) == kReadHeaderSize,
57 socks4_server_response_struct_wrong_size);
59 SOCKSClientSocket::SOCKSClientSocket(
60 scoped_ptr<ClientSocketHandle> transport_socket,
61 const HostResolver::RequestInfo& req_info,
62 RequestPriority priority,
63 HostResolver* host_resolver)
64 : transport_(transport_socket.Pass()),
65 next_state_(STATE_NONE),
66 completed_handshake_(false),
69 was_ever_used_(false),
70 host_resolver_(host_resolver),
71 host_request_info_(req_info),
73 net_log_(transport_->socket()->NetLog()) {}
75 SOCKSClientSocket::~SOCKSClientSocket() {
79 int SOCKSClientSocket::Connect(const CompletionCallback& callback) {
80 DCHECK(transport_.get());
81 DCHECK(transport_->socket());
82 DCHECK_EQ(STATE_NONE, next_state_);
83 DCHECK(user_callback_.is_null());
85 // If already connected, then just return OK.
86 if (completed_handshake_)
89 next_state_ = STATE_RESOLVE_HOST;
91 net_log_.BeginEvent(NetLog::TYPE_SOCKS_CONNECT);
94 if (rv == ERR_IO_PENDING) {
95 user_callback_ = callback;
97 net_log_.EndEventWithNetErrorCode(NetLog::TYPE_SOCKS_CONNECT, rv);
102 void SOCKSClientSocket::Disconnect() {
103 completed_handshake_ = false;
104 host_resolver_.Cancel();
105 transport_->socket()->Disconnect();
107 // Reset other states to make sure they aren't mistakenly used later.
108 // These are the states initialized by Connect().
109 next_state_ = STATE_NONE;
110 user_callback_.Reset();
113 bool SOCKSClientSocket::IsConnected() const {
114 return completed_handshake_ && transport_->socket()->IsConnected();
117 bool SOCKSClientSocket::IsConnectedAndIdle() const {
118 return completed_handshake_ && transport_->socket()->IsConnectedAndIdle();
121 const BoundNetLog& SOCKSClientSocket::NetLog() const {
125 void SOCKSClientSocket::SetSubresourceSpeculation() {
126 if (transport_.get() && transport_->socket()) {
127 transport_->socket()->SetSubresourceSpeculation();
133 void SOCKSClientSocket::SetOmniboxSpeculation() {
134 if (transport_.get() && transport_->socket()) {
135 transport_->socket()->SetOmniboxSpeculation();
141 bool SOCKSClientSocket::WasEverUsed() const {
142 return was_ever_used_;
145 bool SOCKSClientSocket::UsingTCPFastOpen() const {
146 if (transport_.get() && transport_->socket()) {
147 return transport_->socket()->UsingTCPFastOpen();
153 bool SOCKSClientSocket::WasNpnNegotiated() const {
154 if (transport_.get() && transport_->socket()) {
155 return transport_->socket()->WasNpnNegotiated();
161 NextProto SOCKSClientSocket::GetNegotiatedProtocol() const {
162 if (transport_.get() && transport_->socket()) {
163 return transport_->socket()->GetNegotiatedProtocol();
166 return kProtoUnknown;
169 bool SOCKSClientSocket::GetSSLInfo(SSLInfo* ssl_info) {
170 if (transport_.get() && transport_->socket()) {
171 return transport_->socket()->GetSSLInfo(ssl_info);
178 // Read is called by the transport layer above to read. This can only be done
179 // if the SOCKS handshake is complete.
180 int SOCKSClientSocket::Read(IOBuffer* buf, int buf_len,
181 const CompletionCallback& callback) {
182 DCHECK(completed_handshake_);
183 DCHECK_EQ(STATE_NONE, next_state_);
184 DCHECK(user_callback_.is_null());
185 DCHECK(!callback.is_null());
187 int rv = transport_->socket()->Read(
189 base::Bind(&SOCKSClientSocket::OnReadWriteComplete,
190 base::Unretained(this), callback));
192 was_ever_used_ = true;
196 // Write is called by the transport layer. This can only be done if the
197 // SOCKS handshake is complete.
198 int SOCKSClientSocket::Write(IOBuffer* buf, int buf_len,
199 const CompletionCallback& callback) {
200 DCHECK(completed_handshake_);
201 DCHECK_EQ(STATE_NONE, next_state_);
202 DCHECK(user_callback_.is_null());
203 DCHECK(!callback.is_null());
205 int rv = transport_->socket()->Write(
207 base::Bind(&SOCKSClientSocket::OnReadWriteComplete,
208 base::Unretained(this), callback));
210 was_ever_used_ = true;
214 int SOCKSClientSocket::SetReceiveBufferSize(int32 size) {
215 return transport_->socket()->SetReceiveBufferSize(size);
218 int SOCKSClientSocket::SetSendBufferSize(int32 size) {
219 return transport_->socket()->SetSendBufferSize(size);
222 void SOCKSClientSocket::DoCallback(int result) {
223 DCHECK_NE(ERR_IO_PENDING, result);
224 DCHECK(!user_callback_.is_null());
226 // Since Run() may result in Read being called,
227 // clear user_callback_ up front.
228 DVLOG(1) << "Finished setting up SOCKS handshake";
229 base::ResetAndReturn(&user_callback_).Run(result);
232 void SOCKSClientSocket::OnIOComplete(int result) {
233 DCHECK_NE(STATE_NONE, next_state_);
234 int rv = DoLoop(result);
235 if (rv != ERR_IO_PENDING) {
236 net_log_.EndEventWithNetErrorCode(NetLog::TYPE_SOCKS_CONNECT, rv);
241 void SOCKSClientSocket::OnReadWriteComplete(const CompletionCallback& callback,
243 DCHECK_NE(ERR_IO_PENDING, result);
244 DCHECK(!callback.is_null());
247 was_ever_used_ = true;
248 callback.Run(result);
251 int SOCKSClientSocket::DoLoop(int last_io_result) {
252 DCHECK_NE(next_state_, STATE_NONE);
253 int rv = last_io_result;
255 State state = next_state_;
256 next_state_ = STATE_NONE;
258 case STATE_RESOLVE_HOST:
260 rv = DoResolveHost();
262 case STATE_RESOLVE_HOST_COMPLETE:
263 rv = DoResolveHostComplete(rv);
265 case STATE_HANDSHAKE_WRITE:
267 rv = DoHandshakeWrite();
269 case STATE_HANDSHAKE_WRITE_COMPLETE:
270 rv = DoHandshakeWriteComplete(rv);
272 case STATE_HANDSHAKE_READ:
274 rv = DoHandshakeRead();
276 case STATE_HANDSHAKE_READ_COMPLETE:
277 rv = DoHandshakeReadComplete(rv);
280 NOTREACHED() << "bad state";
284 } while (rv != ERR_IO_PENDING && next_state_ != STATE_NONE);
288 int SOCKSClientSocket::DoResolveHost() {
289 next_state_ = STATE_RESOLVE_HOST_COMPLETE;
290 // SOCKS4 only supports IPv4 addresses, so only try getting the IPv4
291 // addresses for the target host.
292 host_request_info_.set_address_family(ADDRESS_FAMILY_IPV4);
293 return host_resolver_.Resolve(
297 base::Bind(&SOCKSClientSocket::OnIOComplete, base::Unretained(this)),
301 int SOCKSClientSocket::DoResolveHostComplete(int result) {
303 // Resolving the hostname failed; fail the request rather than automatically
304 // falling back to SOCKS4a (since it can be confusing to see invalid IP
305 // addresses being sent to the SOCKS4 server when it doesn't support 4A.)
309 next_state_ = STATE_HANDSHAKE_WRITE;
313 // Builds the buffer that is to be sent to the server.
314 const std::string SOCKSClientSocket::BuildHandshakeWriteBuffer() const {
315 SOCKS4ServerRequest request;
316 request.version = kSOCKSVersion4;
317 request.command = kSOCKSStreamRequest;
318 request.nw_port = base::HostToNet16(host_request_info_.port());
320 DCHECK(!addresses_.empty());
321 const IPEndPoint& endpoint = addresses_.front();
323 // We disabled IPv6 results when resolving the hostname, so none of the
324 // results in the list will be IPv6.
325 // TODO(eroman): we only ever use the first address in the list. It would be
326 // more robust to try all the IP addresses we have before
327 // failing the connect attempt.
328 CHECK_EQ(ADDRESS_FAMILY_IPV4, endpoint.GetFamily());
329 CHECK_LE(endpoint.address().size(), sizeof(request.ip));
330 memcpy(&request.ip, &endpoint.address()[0], endpoint.address().size());
332 DVLOG(1) << "Resolved Host is : " << endpoint.ToStringWithoutPort();
334 std::string handshake_data(reinterpret_cast<char*>(&request),
336 handshake_data.append(kEmptyUserId, arraysize(kEmptyUserId));
338 return handshake_data;
341 // Writes the SOCKS handshake data to the underlying socket connection.
342 int SOCKSClientSocket::DoHandshakeWrite() {
343 next_state_ = STATE_HANDSHAKE_WRITE_COMPLETE;
345 if (buffer_.empty()) {
346 buffer_ = BuildHandshakeWriteBuffer();
350 int handshake_buf_len = buffer_.size() - bytes_sent_;
351 DCHECK_GT(handshake_buf_len, 0);
352 handshake_buf_ = new IOBuffer(handshake_buf_len);
353 memcpy(handshake_buf_->data(), &buffer_[bytes_sent_],
355 return transport_->socket()->Write(
356 handshake_buf_.get(),
358 base::Bind(&SOCKSClientSocket::OnIOComplete, base::Unretained(this)));
361 int SOCKSClientSocket::DoHandshakeWriteComplete(int result) {
365 // We ignore the case when result is 0, since the underlying Write
366 // may return spurious writes while waiting on the socket.
368 bytes_sent_ += result;
369 if (bytes_sent_ == buffer_.size()) {
370 next_state_ = STATE_HANDSHAKE_READ;
372 } else if (bytes_sent_ < buffer_.size()) {
373 next_state_ = STATE_HANDSHAKE_WRITE;
375 return ERR_UNEXPECTED;
381 int SOCKSClientSocket::DoHandshakeRead() {
382 next_state_ = STATE_HANDSHAKE_READ_COMPLETE;
384 if (buffer_.empty()) {
388 int handshake_buf_len = kReadHeaderSize - bytes_received_;
389 handshake_buf_ = new IOBuffer(handshake_buf_len);
390 return transport_->socket()->Read(
391 handshake_buf_.get(),
393 base::Bind(&SOCKSClientSocket::OnIOComplete, base::Unretained(this)));
396 int SOCKSClientSocket::DoHandshakeReadComplete(int result) {
400 // The underlying socket closed unexpectedly.
402 return ERR_CONNECTION_CLOSED;
404 if (bytes_received_ + result > kReadHeaderSize) {
405 // TODO(eroman): Describe failure in NetLog.
406 return ERR_SOCKS_CONNECTION_FAILED;
409 buffer_.append(handshake_buf_->data(), result);
410 bytes_received_ += result;
411 if (bytes_received_ < kReadHeaderSize) {
412 next_state_ = STATE_HANDSHAKE_READ;
416 const SOCKS4ServerResponse* response =
417 reinterpret_cast<const SOCKS4ServerResponse*>(buffer_.data());
419 if (response->reserved_null != 0x00) {
420 LOG(ERROR) << "Unknown response from SOCKS server.";
421 return ERR_SOCKS_CONNECTION_FAILED;
424 switch (response->code) {
425 case kServerResponseOk:
426 completed_handshake_ = true;
428 case kServerResponseRejected:
429 LOG(ERROR) << "SOCKS request rejected or failed";
430 return ERR_SOCKS_CONNECTION_FAILED;
431 case kServerResponseNotReachable:
432 LOG(ERROR) << "SOCKS request failed because client is not running "
433 << "identd (or not reachable from the server)";
434 return ERR_SOCKS_CONNECTION_HOST_UNREACHABLE;
435 case kServerResponseMismatchedUserId:
436 LOG(ERROR) << "SOCKS request failed because client's identd could "
437 << "not confirm the user ID string in the request";
438 return ERR_SOCKS_CONNECTION_FAILED;
440 LOG(ERROR) << "SOCKS server sent unknown response";
441 return ERR_SOCKS_CONNECTION_FAILED;
444 // Note: we ignore the last 6 bytes as specified by the SOCKS protocol
447 int SOCKSClientSocket::GetPeerAddress(IPEndPoint* address) const {
448 return transport_->socket()->GetPeerAddress(address);
451 int SOCKSClientSocket::GetLocalAddress(IPEndPoint* address) const {
452 return transport_->socket()->GetLocalAddress(address);