// Copyright (c) 2008 The Chromium Authors. All rights reserved. Use of this
// source code is governed by a BSD-style license that can be found in the
// LICENSE file.
#include "net/ftp/ftp_network_transaction.h"
#include "base/compiler_specific.h"
#include "base/histogram.h"
#include "base/string_util.h"
#include "net/base/connection_type_histograms.h"
#include "net/base/escape.h"
#include "net/base/load_log.h"
#include "net/base/net_errors.h"
#include "net/base/net_util.h"
#include "net/ftp/ftp_network_session.h"
#include "net/ftp/ftp_request_info.h"
#include "net/ftp/ftp_util.h"
#include "net/socket/client_socket.h"
#include "net/socket/client_socket_factory.h"
// TODO(ibrar): Try to avoid sscanf.
#if !defined(COMPILER_MSVC)
#define sscanf_s sscanf
#endif
const char kCRLF[] = "\r\n";
const int kCtrlBufLen = 1024;
namespace {
// Returns true if |input| can be safely used as a part of FTP command.
bool IsValidFTPCommandString(const std::string& input) {
// RFC 959 only allows ASCII strings, but at least Firefox can send non-ASCII
// characters in the command if the request path contains them. To be
// compatible, we do the same and allow non-ASCII characters in a command.
// Protect agains newline injection attack.
if (input.find_first_of("\r\n") != std::string::npos)
return false;
return true;
}
} // namespace
namespace net {
FtpNetworkTransaction::FtpNetworkTransaction(
FtpNetworkSession* session,
ClientSocketFactory* socket_factory)
: command_sent_(COMMAND_NONE),
ALLOW_THIS_IN_INITIALIZER_LIST(
io_callback_(this, &FtpNetworkTransaction::OnIOComplete)),
user_callback_(NULL),
session_(session),
request_(NULL),
resolver_(session->host_resolver()),
read_ctrl_buf_(new IOBuffer(kCtrlBufLen)),
ctrl_response_buffer_(new FtpCtrlResponseBuffer()),
read_data_buf_len_(0),
file_data_len_(0),
last_error_(OK),
system_type_(SYSTEM_TYPE_UNKNOWN),
retr_failed_(false),
data_connection_port_(0),
socket_factory_(socket_factory),
next_state_(STATE_NONE) {
}
FtpNetworkTransaction::~FtpNetworkTransaction() {
}
int FtpNetworkTransaction::Start(const FtpRequestInfo* request_info,
CompletionCallback* callback,
LoadLog* load_log) {
load_log_ = load_log;
request_ = request_info;
if (request_->url.has_username()) {
GetIdentityFromURL(request_->url, &username_, &password_);
} else {
username_ = L"anonymous";
password_ = L"chrome@example.com";
}
next_state_ = STATE_CTRL_INIT;
int rv = DoLoop(OK);
if (rv == ERR_IO_PENDING)
user_callback_ = callback;
return rv;
}
int FtpNetworkTransaction::Stop(int error) {
if (command_sent_ == COMMAND_QUIT)
return error;
next_state_ = STATE_CTRL_WRITE_QUIT;
last_error_ = error;
return OK;
}
int FtpNetworkTransaction::RestartWithAuth(const std::wstring& username,
const std::wstring& password,
CompletionCallback* callback) {
ResetStateForRestart();
username_ = username;
password_ = password;
next_state_ = STATE_CTRL_INIT;
int rv = DoLoop(OK);
if (rv == ERR_IO_PENDING)
user_callback_ = callback;
return rv;
}
int FtpNetworkTransaction::RestartIgnoringLastError(
CompletionCallback* callback) {
return ERR_FAILED;
}
int FtpNetworkTransaction::Read(IOBuffer* buf,
int buf_len,
CompletionCallback* callback) {
DCHECK(buf);
DCHECK_GT(buf_len, 0);
read_data_buf_ = buf;
read_data_buf_len_ = buf_len;
next_state_ = STATE_DATA_READ;
int rv = DoLoop(OK);
if (rv == ERR_IO_PENDING)
user_callback_ = callback;
return rv;
}
const FtpResponseInfo* FtpNetworkTransaction::GetResponseInfo() const {
return &response_;
}
LoadState FtpNetworkTransaction::GetLoadState() const {
if (next_state_ == STATE_CTRL_RESOLVE_HOST_COMPLETE)
return LOAD_STATE_RESOLVING_HOST;
if (next_state_ == STATE_CTRL_CONNECT_COMPLETE ||
next_state_ == STATE_DATA_CONNECT_COMPLETE)
return LOAD_STATE_CONNECTING;
if (next_state_ == STATE_DATA_READ_COMPLETE)
return LOAD_STATE_READING_RESPONSE;
if (command_sent_ == COMMAND_RETR && read_data_buf_.get())
return LOAD_STATE_READING_RESPONSE;
if (command_sent_ == COMMAND_QUIT)
return LOAD_STATE_IDLE;
if (command_sent_ != COMMAND_NONE)
return LOAD_STATE_SENDING_REQUEST;
return LOAD_STATE_IDLE;
}
uint64 FtpNetworkTransaction::GetUploadProgress() const {
return 0;
}
// Used to prepare and send FTP command.
int FtpNetworkTransaction::SendFtpCommand(const std::string& command,
Command cmd) {
// If we send a new command when we still have unprocessed responses
// for previous commands, the response receiving code will have no way to know
// which responses are for which command.
DCHECK(!ctrl_response_buffer_->ResponseAvailable());
DCHECK(!write_command_buf_);
DCHECK(!write_buf_);
if (!IsValidFTPCommandString(command)) {
// Callers should validate the command themselves and return a more specific
// error code.
NOTREACHED();
return Stop(ERR_UNEXPECTED);
}
command_sent_ = cmd;
write_command_buf_ = new IOBufferWithSize(command.length() + 2);
write_buf_ = new DrainableIOBuffer(write_command_buf_,
write_command_buf_->size());
memcpy(write_command_buf_->data(), command.data(), command.length());
memcpy(write_command_buf_->data() + command.length(), kCRLF, 2);
next_state_ = STATE_CTRL_WRITE;
return OK;
}
// static
FtpNetworkTransaction::ErrorClass FtpNetworkTransaction::GetErrorClass(
int response_code) {
if (response_code >= 100 && response_code <= 199)
return ERROR_CLASS_INITIATED;
if (response_code >= 200 && response_code <= 299)
return ERROR_CLASS_OK;
if (response_code >= 300 && response_code <= 399)
return ERROR_CLASS_INFO_NEEDED;
if (response_code >= 400 && response_code <= 499)
return ERROR_CLASS_TRANSIENT_ERROR;
if (response_code >= 500 && response_code <= 599)
return ERROR_CLASS_PERMANENT_ERROR;
// We should not be called on invalid error codes.
NOTREACHED();
return ERROR_CLASS_PERMANENT_ERROR;
}
int FtpNetworkTransaction::ProcessCtrlResponse() {
FtpCtrlResponse response = ctrl_response_buffer_->PopResponse();
int rv = OK;
switch (command_sent_) {
case COMMAND_NONE:
// TODO(phajdan.jr): Check for errors in the welcome message.
next_state_ = STATE_CTRL_WRITE_USER;
break;
case COMMAND_USER:
rv = ProcessResponseUSER(response);
break;
case COMMAND_PASS:
rv = ProcessResponsePASS(response);
break;
case COMMAND_ACCT:
rv = ProcessResponseACCT(response);
break;
case COMMAND_SYST:
rv = ProcessResponseSYST(response);
break;
case COMMAND_PWD:
rv = ProcessResponsePWD(response);
break;
case COMMAND_TYPE:
rv = ProcessResponseTYPE(response);
break;
case COMMAND_PASV:
rv = ProcessResponsePASV(response);
break;
case COMMAND_SIZE:
rv = ProcessResponseSIZE(response);
break;
case COMMAND_RETR:
rv = ProcessResponseRETR(response);
break;
case COMMAND_CWD:
rv = ProcessResponseCWD(response);
break;
case COMMAND_MLSD:
rv = ProcessResponseMLSD(response);
break;
case COMMAND_LIST:
rv = ProcessResponseLIST(response);
break;
case COMMAND_MDTM:
rv = ProcessResponseMDTM(response);
break;
case COMMAND_QUIT:
rv = ProcessResponseQUIT(response);
break;
default:
LOG(DFATAL) << "Unexpected value of command_sent_: " << command_sent_;
return ERR_UNEXPECTED;
}
// We may get multiple responses for some commands,
// see http://crbug.com/18036.
while (ctrl_response_buffer_->ResponseAvailable() && rv == OK) {
response = ctrl_response_buffer_->PopResponse();
switch (command_sent_) {
case COMMAND_RETR:
rv = ProcessResponseRETR(response);
break;
case COMMAND_MLSD:
rv = ProcessResponseMLSD(response);
break;
case COMMAND_LIST:
rv = ProcessResponseLIST(response);
break;
default:
// Multiple responses for other commands are invalid.
return Stop(ERR_INVALID_RESPONSE);
}
}
return rv;
}
void FtpNetworkTransaction::ResetStateForRestart() {
command_sent_ = COMMAND_NONE;
user_callback_ = NULL;
response_ = FtpResponseInfo();
read_ctrl_buf_ = new IOBuffer(kCtrlBufLen);
ctrl_response_buffer_.reset(new FtpCtrlResponseBuffer());
read_data_buf_ = NULL;
read_data_buf_len_ = 0;
file_data_len_ = 0;
if (write_buf_)
write_buf_->SetOffset(0);
last_error_ = OK;
retr_failed_ = false;
data_connection_port_ = 0;
ctrl_socket_.reset();
data_socket_.reset();
next_state_ = STATE_NONE;
}
void FtpNetworkTransaction::DoCallback(int rv) {
DCHECK(rv != ERR_IO_PENDING);
DCHECK(user_callback_);
// Since Run may result in Read being called, clear callback_ up front.
CompletionCallback* c = user_callback_;
user_callback_ = NULL;
c->Run(rv);
}
void FtpNetworkTransaction::OnIOComplete(int result) {
int rv = DoLoop(result);
if (rv != ERR_IO_PENDING)
DoCallback(rv);
}
std::string FtpNetworkTransaction::GetRequestPathForFtpCommand(
bool is_directory) const {
std::string path(current_remote_directory_);
if (request_->url.has_path())
path.append(request_->url.path());
// Make sure that if the path is expected to be a file, it won't end
// with a trailing slash.
if (!is_directory && path.length() > 1 && path[path.length() - 1] == '/')
path.erase(path.length() - 1);
UnescapeRule::Type unescape_rules = UnescapeRule::SPACES |
UnescapeRule::URL_SPECIAL_CHARS;
// This may unescape to non-ASCII characters, but we allow that. See the
// comment for IsValidFTPCommandString.
path = UnescapeURLComponent(path, unescape_rules);
if (system_type_ == SYSTEM_TYPE_VMS) {
if (is_directory)
path = FtpUtil::UnixDirectoryPathToVMS(path);
else
path = FtpUtil::UnixFilePathToVMS(path);
}
DCHECK(IsValidFTPCommandString(path));
return path;
}
int FtpNetworkTransaction::DoLoop(int result) {
DCHECK(next_state_ != STATE_NONE);
int rv = result;
do {
State state = next_state_;
next_state_ = STATE_NONE;
switch (state) {
case STATE_CTRL_INIT:
DCHECK(rv == OK);
rv = DoCtrlInit();
break;
case STATE_CTRL_INIT_COMPLETE:
rv = DoCtrlInitComplete(rv);
break;
case STATE_CTRL_RESOLVE_HOST:
DCHECK(rv == OK);
rv = DoCtrlResolveHost();
break;
case STATE_CTRL_RESOLVE_HOST_COMPLETE:
rv = DoCtrlResolveHostComplete(rv);
break;
case STATE_CTRL_CONNECT:
DCHECK(rv == OK);
rv = DoCtrlConnect();
break;
case STATE_CTRL_CONNECT_COMPLETE:
rv = DoCtrlConnectComplete(rv);
break;
case STATE_CTRL_READ:
DCHECK(rv == OK);
rv = DoCtrlRead();
break;
case STATE_CTRL_READ_COMPLETE:
rv = DoCtrlReadComplete(rv);
break;
case STATE_CTRL_WRITE:
DCHECK(rv == OK);
rv = DoCtrlWrite();
break;
case STATE_CTRL_WRITE_COMPLETE:
rv = DoCtrlWriteComplete(rv);
break;
case STATE_CTRL_WRITE_USER:
DCHECK(rv == OK);
rv = DoCtrlWriteUSER();
break;
case STATE_CTRL_WRITE_PASS:
DCHECK(rv == OK);
rv = DoCtrlWritePASS();
break;
case STATE_CTRL_WRITE_SYST:
DCHECK(rv == OK);
rv = DoCtrlWriteSYST();
break;
case STATE_CTRL_WRITE_ACCT:
DCHECK(rv == OK);
rv = DoCtrlWriteACCT();
break;
case STATE_CTRL_WRITE_PWD:
DCHECK(rv == OK);
rv = DoCtrlWritePWD();
break;
case STATE_CTRL_WRITE_TYPE:
DCHECK(rv == OK);
rv = DoCtrlWriteTYPE();
break;
case STATE_CTRL_WRITE_PASV:
DCHECK(rv == OK);
rv = DoCtrlWritePASV();
break;
case STATE_CTRL_WRITE_RETR:
DCHECK(rv == OK);
rv = DoCtrlWriteRETR();
break;
case STATE_CTRL_WRITE_SIZE:
DCHECK(rv == OK);
rv = DoCtrlWriteSIZE();
break;
case STATE_CTRL_WRITE_CWD:
DCHECK(rv == OK);
rv = DoCtrlWriteCWD();
break;
case STATE_CTRL_WRITE_MLSD:
DCHECK(rv == 0);
rv = DoCtrlWriteMLSD();
break;
case STATE_CTRL_WRITE_LIST:
DCHECK(rv == OK);
rv = DoCtrlWriteLIST();
break;
case STATE_CTRL_WRITE_MDTM:
DCHECK(rv == OK);
rv = DoCtrlWriteMDTM();
break;
case STATE_CTRL_WRITE_QUIT:
DCHECK(rv == OK);
rv = DoCtrlWriteQUIT();
break;
case STATE_DATA_CONNECT:
DCHECK(rv == OK);
rv = DoDataConnect();
break;
case STATE_DATA_CONNECT_COMPLETE:
rv = DoDataConnectComplete(rv);
break;
case STATE_DATA_READ:
DCHECK(rv == OK);
rv = DoDataRead();
break;
case STATE_DATA_READ_COMPLETE:
rv = DoDataReadComplete(rv);
break;
default:
NOTREACHED() << "bad state";
rv = ERR_UNEXPECTED;
break;
}
} while (rv != ERR_IO_PENDING && next_state_ != STATE_NONE);
return rv;
}
// TODO(ibrar): Yet to see if we need any intialization
int FtpNetworkTransaction::DoCtrlInit() {
next_state_ = STATE_CTRL_INIT_COMPLETE;
return OK;
}
int FtpNetworkTransaction::DoCtrlInitComplete(int result) {
next_state_ = STATE_CTRL_RESOLVE_HOST;
return OK;
}
int FtpNetworkTransaction::DoCtrlResolveHost() {
next_state_ = STATE_CTRL_RESOLVE_HOST_COMPLETE;
std::string host;
int port;
host = request_->url.host();
port = request_->url.EffectiveIntPort();
HostResolver::RequestInfo info(host, port);
// No known referrer.
return resolver_.Resolve(info, &addresses_, &io_callback_, load_log_);
}
int FtpNetworkTransaction::DoCtrlResolveHostComplete(int result) {
if (result == OK)
next_state_ = STATE_CTRL_CONNECT;
return result;
}
int FtpNetworkTransaction::DoCtrlConnect() {
next_state_ = STATE_CTRL_CONNECT_COMPLETE;
ctrl_socket_.reset(socket_factory_->CreateTCPClientSocket(addresses_));
return ctrl_socket_->Connect(&io_callback_, load_log_);
}
int FtpNetworkTransaction::DoCtrlConnectComplete(int result) {
if (result == OK)
next_state_ = STATE_CTRL_READ;
return result;
}
int FtpNetworkTransaction::DoCtrlRead() {
next_state_ = STATE_CTRL_READ_COMPLETE;
return ctrl_socket_->Read(
read_ctrl_buf_,
kCtrlBufLen,
&io_callback_);
}
int FtpNetworkTransaction::DoCtrlReadComplete(int result) {
if (result == 0) {
// Some servers (for example Pure-FTPd) apparently close the control
// connection when anonymous login is not permitted. For more details
// see http://crbug.com/25023.
if (command_sent_ == COMMAND_USER && username_ == L"anonymous")
response_.needs_auth = true;
return Stop(ERR_EMPTY_RESPONSE);
}
if (result < 0)
return Stop(result);
ctrl_response_buffer_->ConsumeData(read_ctrl_buf_->data(), result);
if (!ctrl_response_buffer_->ResponseAvailable()) {
// Read more data from the control socket.
next_state_ = STATE_CTRL_READ;
return OK;
}
return ProcessCtrlResponse();
}
int FtpNetworkTransaction::DoCtrlWrite() {
next_state_ = STATE_CTRL_WRITE_COMPLETE;
return ctrl_socket_->Write(write_buf_,
write_buf_->BytesRemaining(),
&io_callback_);
}
int FtpNetworkTransaction::DoCtrlWriteComplete(int result) {
if (result < 0)
return result;
write_buf_->DidConsume(result);
if (write_buf_->BytesRemaining() == 0) {
// Clear the write buffer.
write_buf_ = NULL;
write_command_buf_ = NULL;
next_state_ = STATE_CTRL_READ;
} else {
next_state_ = STATE_CTRL_WRITE;
}
return OK;
}
// FTP Commands and responses
// USER Command.
int FtpNetworkTransaction::DoCtrlWriteUSER() {
std::string command = "USER " + WideToUTF8(username_);
if (!IsValidFTPCommandString(command))
return Stop(ERR_MALFORMED_IDENTITY);
next_state_ = STATE_CTRL_READ;
return SendFtpCommand(command, COMMAND_USER);
}
int FtpNetworkTransaction::ProcessResponseUSER(
const FtpCtrlResponse& response) {
switch (GetErrorClass(response.status_code)) {
case ERROR_CLASS_OK:
next_state_ = STATE_CTRL_WRITE_SYST;
break;
case ERROR_CLASS_INFO_NEEDED:
next_state_ = STATE_CTRL_WRITE_PASS;
break;
case ERROR_CLASS_TRANSIENT_ERROR:
if (response.status_code == 421)
return Stop(ERR_FAILED);
break;
case ERROR_CLASS_PERMANENT_ERROR:
return Stop(ERR_FAILED);
default:
NOTREACHED();
return Stop(ERR_UNEXPECTED);
}
return OK;
}
// PASS command.
int FtpNetworkTransaction::DoCtrlWritePASS() {
std::string command = "PASS " + WideToUTF8(password_);
if (!IsValidFTPCommandString(command))
return Stop(ERR_MALFORMED_IDENTITY);
next_state_ = STATE_CTRL_READ;
return SendFtpCommand(command, COMMAND_PASS);
}
int FtpNetworkTransaction::ProcessResponsePASS(
const FtpCtrlResponse& response) {
switch (GetErrorClass(response.status_code)) {
case ERROR_CLASS_OK:
next_state_ = STATE_CTRL_WRITE_SYST;
break;
case ERROR_CLASS_INFO_NEEDED:
next_state_ = STATE_CTRL_WRITE_ACCT;
break;
case ERROR_CLASS_TRANSIENT_ERROR:
if (response.status_code == 421) {
// TODO(ibrar): Retry here.
}
return Stop(ERR_FAILED);
case ERROR_CLASS_PERMANENT_ERROR:
if (response.status_code == 503) {
next_state_ = STATE_CTRL_WRITE_USER;
} else {
response_.needs_auth = true;
return Stop(ERR_FAILED);
}
break;
default:
NOTREACHED();
return Stop(ERR_UNEXPECTED);
}
return OK;
}
// SYST command.
int FtpNetworkTransaction::DoCtrlWriteSYST() {
std::string command = "SYST";
next_state_ = STATE_CTRL_READ;
return SendFtpCommand(command, COMMAND_SYST);
}
int FtpNetworkTransaction::ProcessResponseSYST(
const FtpCtrlResponse& response) {
switch (GetErrorClass(response.status_code)) {
case ERROR_CLASS_INITIATED:
return Stop(ERR_INVALID_RESPONSE);
case ERROR_CLASS_OK: {
// All important info should be on the first line.
std::string line = response.lines[0];
// The response should be ASCII, which allows us to do case-insensitive
// comparisons easily. If it is not ASCII, we leave the system type
// as unknown.
if (IsStringASCII(line)) {
line = StringToLowerASCII(line);
// The "magic" strings we test for below have been gathered by an
// empirical study.
if (line.find("l8") != std::string::npos ||
line.find("unix") != std::string::npos ||
line.find("bsd") != std::string::npos) {
system_type_ = SYSTEM_TYPE_UNIX;
} else if (line.find("win32") != std::string::npos ||
line.find("windows") != std::string::npos) {
system_type_ = SYSTEM_TYPE_WINDOWS;
} else if (line.find("os/2") != std::string::npos) {
system_type_ = SYSTEM_TYPE_OS2;
} else if (line.find("vms") != std::string::npos) {
system_type_ = SYSTEM_TYPE_VMS;
}
}
next_state_ = STATE_CTRL_WRITE_PWD;
break;
}
case ERROR_CLASS_INFO_NEEDED:
return Stop(ERR_INVALID_RESPONSE);
case ERROR_CLASS_TRANSIENT_ERROR:
return Stop(ERR_FAILED);
case ERROR_CLASS_PERMANENT_ERROR:
// Server does not recognize the SYST command so proceed.
next_state_ = STATE_CTRL_WRITE_PWD;
break;
default:
NOTREACHED();
return Stop(ERR_UNEXPECTED);
}
return OK;
}
// PWD command.
int FtpNetworkTransaction::DoCtrlWritePWD() {
std::string command = "PWD";
next_state_ = STATE_CTRL_READ;
return SendFtpCommand(command, COMMAND_PWD);
}
int FtpNetworkTransaction::ProcessResponsePWD(const FtpCtrlResponse& response) {
switch (GetErrorClass(response.status_code)) {
case ERROR_CLASS_INITIATED:
return Stop(ERR_INVALID_RESPONSE);
case ERROR_CLASS_OK: {
// The info we look for should be on the first line.
std::string line = response.lines[0];
if (line.empty())
return Stop(ERR_INVALID_RESPONSE);
std::string::size_type quote_pos = line.find('"');
if (quote_pos != std::string::npos) {
line = line.substr(quote_pos + 1);
quote_pos = line.find('"');
if (quote_pos == std::string::npos)
return Stop(ERR_INVALID_RESPONSE);
line = line.substr(0, quote_pos);
}
if (system_type_ == SYSTEM_TYPE_VMS)
line = FtpUtil::VMSPathToUnix(line);
if (line[line.length() - 1] == '/')
line.erase(line.length() - 1);
current_remote_directory_ = line;
next_state_ = STATE_CTRL_WRITE_TYPE;
break;
}
case ERROR_CLASS_INFO_NEEDED:
return Stop(ERR_INVALID_RESPONSE);
case ERROR_CLASS_TRANSIENT_ERROR:
return Stop(ERR_FAILED);
case ERROR_CLASS_PERMANENT_ERROR:
return Stop(ERR_FAILED);
default:
NOTREACHED();
return Stop(ERR_UNEXPECTED);
}
return OK;
}
// TYPE command.
int FtpNetworkTransaction::DoCtrlWriteTYPE() {
std::string command = "TYPE I";
next_state_ = STATE_CTRL_READ;
return SendFtpCommand(command, COMMAND_TYPE);
}
int FtpNetworkTransaction::ProcessResponseTYPE(
const FtpCtrlResponse& response) {
switch (GetErrorClass(response.status_code)) {
case ERROR_CLASS_INITIATED:
return Stop(ERR_INVALID_RESPONSE);
case ERROR_CLASS_OK:
next_state_ = STATE_CTRL_WRITE_PASV;
break;
case ERROR_CLASS_INFO_NEEDED:
return Stop(ERR_INVALID_RESPONSE);
case ERROR_CLASS_TRANSIENT_ERROR:
return Stop(ERR_FAILED);
case ERROR_CLASS_PERMANENT_ERROR:
return Stop(ERR_FAILED);
default:
NOTREACHED();
return Stop(ERR_UNEXPECTED);
}
return OK;
}
// ACCT command.
int FtpNetworkTransaction::DoCtrlWriteACCT() {
std::string command = "ACCT noaccount";
next_state_ = STATE_CTRL_READ;
return SendFtpCommand(command, COMMAND_ACCT);
}
int FtpNetworkTransaction::ProcessResponseACCT(
const FtpCtrlResponse& response) {
switch (GetErrorClass(response.status_code)) {
case ERROR_CLASS_INITIATED:
return Stop(ERR_INVALID_RESPONSE);
case ERROR_CLASS_OK:
next_state_ = STATE_CTRL_WRITE_SYST;
break;
case ERROR_CLASS_INFO_NEEDED:
return Stop(ERR_INVALID_RESPONSE);
case ERROR_CLASS_TRANSIENT_ERROR:
return Stop(ERR_FAILED);
case ERROR_CLASS_PERMANENT_ERROR:
return Stop(ERR_FAILED);
default:
NOTREACHED();
return Stop(ERR_UNEXPECTED);
}
return OK;
}
// PASV command
int FtpNetworkTransaction::DoCtrlWritePASV() {
std::string command = "PASV";
next_state_ = STATE_CTRL_READ;
return SendFtpCommand(command, COMMAND_PASV);
}
// There are two way we can receive IP address and port.
// TODO(phajdan.jr): Figure out how this should work for IPv6.
// (127,0,0,1,23,21) IP address and port encapsulated in ().
// 127,0,0,1,23,21 IP address and port without ().
int FtpNetworkTransaction::ProcessResponsePASV(
const FtpCtrlResponse& response) {
switch (GetErrorClass(response.status_code)) {
case ERROR_CLASS_INITIATED:
return Stop(ERR_INVALID_RESPONSE);
case ERROR_CLASS_OK:
const char* ptr;
int i0, i1, i2, i3, p0, p1;
if (response.lines.size() != 1)
return Stop(ERR_INVALID_RESPONSE);
ptr = response.lines[0].c_str(); // Try with bracket.
while (*ptr && *ptr != '(')
++ptr;
if (*ptr) {
++ptr;
} else {
ptr = response.lines[0].c_str(); // Try without bracket.
while (*ptr && *ptr != ',')
++ptr;
while (*ptr && *ptr != ' ')
--ptr;
}
if (sscanf_s(ptr, "%d,%d,%d,%d,%d,%d",
&i0, &i1, &i2, &i3, &p0, &p1) == 6) {
// Ignore the IP address supplied in the response. We are always going
// to connect back to the same server to prevent FTP PASV port scanning.
data_connection_port_ = (p0 << 8) + p1;
if (data_connection_port_ < 1024 ||
!IsPortAllowedByFtp(data_connection_port_))
return Stop(ERR_UNSAFE_PORT);
next_state_ = STATE_DATA_CONNECT;
} else {
return Stop(ERR_INVALID_RESPONSE);
}
break;
case ERROR_CLASS_INFO_NEEDED:
return Stop(ERR_INVALID_RESPONSE);
case ERROR_CLASS_TRANSIENT_ERROR:
return Stop(ERR_FAILED);
case ERROR_CLASS_PERMANENT_ERROR:
return Stop(ERR_FAILED);
default:
NOTREACHED();
return Stop(ERR_UNEXPECTED);
}
return OK;
}
// SIZE command
int FtpNetworkTransaction::DoCtrlWriteSIZE() {
std::string command = "SIZE " + GetRequestPathForFtpCommand(false);
next_state_ = STATE_CTRL_READ;
return SendFtpCommand(command, COMMAND_SIZE);
}
int FtpNetworkTransaction::ProcessResponseSIZE(
const FtpCtrlResponse& response) {
switch (GetErrorClass(response.status_code)) {
case ERROR_CLASS_INITIATED:
break;
case ERROR_CLASS_OK:
if (response.lines.size() != 1)
return Stop(ERR_INVALID_RESPONSE);
if (!StringToInt(response.lines[0], &file_data_len_))
return Stop(ERR_INVALID_RESPONSE);
if (file_data_len_ < 0)
return Stop(ERR_INVALID_RESPONSE);
break;
case ERROR_CLASS_INFO_NEEDED:
break;
case ERROR_CLASS_TRANSIENT_ERROR:
break;
case ERROR_CLASS_PERMANENT_ERROR:
break;
default:
NOTREACHED();
return Stop(ERR_UNEXPECTED);
}
next_state_ = STATE_CTRL_WRITE_MDTM;
return OK;
}
// RETR command
int FtpNetworkTransaction::DoCtrlWriteRETR() {
std::string command = "RETR " + GetRequestPathForFtpCommand(false);
next_state_ = STATE_CTRL_READ;
return SendFtpCommand(command, COMMAND_RETR);
}
int FtpNetworkTransaction::ProcessResponseRETR(
const FtpCtrlResponse& response) {
switch (GetErrorClass(response.status_code)) {
case ERROR_CLASS_INITIATED:
// We want the client to start reading the response at this point.
// It got here either through Start or RestartWithAuth. We want that
// method to complete. Not setting next state here will make DoLoop exit
// and in turn make Start/RestartWithAuth complete.
break;
case ERROR_CLASS_OK:
next_state_ = STATE_CTRL_WRITE_QUIT;
break;
case ERROR_CLASS_INFO_NEEDED:
next_state_ = STATE_CTRL_WRITE_PASV;
break;
case ERROR_CLASS_TRANSIENT_ERROR:
if (response.status_code == 421 || response.status_code == 425 ||
response.status_code == 426)
return Stop(ERR_FAILED);
return ERR_FAILED; // TODO(ibrar): Retry here.
case ERROR_CLASS_PERMANENT_ERROR:
// Code 550 means "Failed to open file". Other codes are unrelated,
// like "Not logged in" etc.
if (response.status_code != 550)
return Stop(ERR_FAILED);
DCHECK(!retr_failed_); // Should not get here twice.
retr_failed_ = true;
// It's possible that RETR failed because the path is a directory.
// We're going to try CWD next, but first send a PASV one more time,
// because some FTP servers, including FileZilla, require that.
// See http://crbug.com/25316.
next_state_ = STATE_CTRL_WRITE_PASV;
break;
default:
NOTREACHED();
return Stop(ERR_UNEXPECTED);
}
return OK;
}
// MDMT command
int FtpNetworkTransaction::DoCtrlWriteMDTM() {
std::string command = "MDTM " + GetRequestPathForFtpCommand(false);
next_state_ = STATE_CTRL_READ;
return SendFtpCommand(command, COMMAND_MDTM);
}
int FtpNetworkTransaction::ProcessResponseMDTM(
const FtpCtrlResponse& response) {
switch (GetErrorClass(response.status_code)) {
case ERROR_CLASS_INITIATED:
return Stop(ERR_FAILED);
case ERROR_CLASS_OK:
next_state_ = STATE_CTRL_WRITE_RETR;
break;
case ERROR_CLASS_INFO_NEEDED:
return Stop(ERR_FAILED);
case ERROR_CLASS_TRANSIENT_ERROR:
return Stop(ERR_FAILED);
case ERROR_CLASS_PERMANENT_ERROR:
next_state_ = STATE_CTRL_WRITE_RETR;
break;
default:
NOTREACHED();
return Stop(ERR_UNEXPECTED);
}
return OK;
}
// CWD command
int FtpNetworkTransaction::DoCtrlWriteCWD() {
std::string command = "CWD " + GetRequestPathForFtpCommand(true);
next_state_ = STATE_CTRL_READ;
return SendFtpCommand(command, COMMAND_CWD);
}
int FtpNetworkTransaction::ProcessResponseCWD(const FtpCtrlResponse& response) {
switch (GetErrorClass(response.status_code)) {
case ERROR_CLASS_INITIATED:
return Stop(ERR_INVALID_RESPONSE);
case ERROR_CLASS_OK:
next_state_ = STATE_CTRL_WRITE_MLSD;
break;
case ERROR_CLASS_INFO_NEEDED:
return Stop(ERR_INVALID_RESPONSE);
case ERROR_CLASS_TRANSIENT_ERROR:
return Stop(ERR_FAILED);
case ERROR_CLASS_PERMANENT_ERROR:
if (retr_failed_ && response.status_code == 550) {
// Both RETR and CWD failed with codes 550. That means that the path
// we're trying to access is not a file, and not a directory. The most
// probable interpretation is that it doesn't exist (with FTP we can't
// be sure).
return Stop(ERR_FILE_NOT_FOUND);
}
return Stop(ERR_FAILED);
default:
NOTREACHED();
return Stop(ERR_UNEXPECTED);
}
return OK;
}
// MLSD command
int FtpNetworkTransaction::DoCtrlWriteMLSD() {
next_state_ = STATE_CTRL_READ;
return SendFtpCommand("MLSD", COMMAND_MLSD);
}
int FtpNetworkTransaction::ProcessResponseMLSD(
const FtpCtrlResponse& response) {
switch (GetErrorClass(response.status_code)) {
case ERROR_CLASS_INITIATED:
response_.is_directory_listing = true;
next_state_ = STATE_CTRL_READ;
break;
case ERROR_CLASS_OK:
response_.is_directory_listing = true;
next_state_ = STATE_CTRL_WRITE_QUIT;
break;
case ERROR_CLASS_INFO_NEEDED:
return Stop(ERR_INVALID_RESPONSE);
case ERROR_CLASS_TRANSIENT_ERROR:
case ERROR_CLASS_PERMANENT_ERROR:
// Fallback to the LIST command, more widely supported,
// but without a specified output format.
next_state_ = STATE_CTRL_WRITE_LIST;
break;
default:
NOTREACHED();
return Stop(ERR_UNEXPECTED);
}
return OK;
}
// LIST command
int FtpNetworkTransaction::DoCtrlWriteLIST() {
std::string command(system_type_ == SYSTEM_TYPE_VMS ? "LIST *.*;0" : "LIST");
next_state_ = STATE_CTRL_READ;
return SendFtpCommand(command, COMMAND_LIST);
}
int FtpNetworkTransaction::ProcessResponseLIST(
const FtpCtrlResponse& response) {
switch (GetErrorClass(response.status_code)) {
case ERROR_CLASS_INITIATED:
response_.is_directory_listing = true;
next_state_ = STATE_CTRL_READ;
break;
case ERROR_CLASS_OK:
response_.is_directory_listing = true;
next_state_ = STATE_CTRL_WRITE_QUIT;
break;
case ERROR_CLASS_INFO_NEEDED:
return Stop(ERR_INVALID_RESPONSE);
case ERROR_CLASS_TRANSIENT_ERROR:
return Stop(ERR_FAILED);
case ERROR_CLASS_PERMANENT_ERROR:
return Stop(ERR_FAILED);
default:
NOTREACHED();
return Stop(ERR_UNEXPECTED);
}
return OK;
}
// QUIT command
int FtpNetworkTransaction::DoCtrlWriteQUIT() {
std::string command = "QUIT";
next_state_ = STATE_CTRL_READ;
return SendFtpCommand(command, COMMAND_QUIT);
}
int FtpNetworkTransaction::ProcessResponseQUIT(
const FtpCtrlResponse& response) {
ctrl_socket_->Disconnect();
return last_error_;
}
// Data Connection
int FtpNetworkTransaction::DoDataConnect() {
next_state_ = STATE_DATA_CONNECT_COMPLETE;
AddressList data_addresses;
// TODO(phajdan.jr): Use exactly same IP address as the control socket.
// If the DNS name resolves to several different IPs, and they are different
// physical servers, this will break. However, that configuration is very rare
// in practice.
data_addresses.Copy(addresses_.head());
data_addresses.SetPort(data_connection_port_);
data_socket_.reset(socket_factory_->CreateTCPClientSocket(data_addresses));
return data_socket_->Connect(&io_callback_, load_log_);
}
int FtpNetworkTransaction::DoDataConnectComplete(int result) {
RecordDataConnectionError(result);
if (retr_failed_) {
next_state_ = STATE_CTRL_WRITE_CWD;
} else {
next_state_ = STATE_CTRL_WRITE_SIZE;
}
return OK;
}
int FtpNetworkTransaction::DoDataRead() {
DCHECK(read_data_buf_);
DCHECK_GT(read_data_buf_len_, 0);
if (data_socket_ == NULL || !data_socket_->IsConnected()) {
// If we don't destroy the data socket completely, some servers will wait
// for us (http://crbug.com/21127). The half-closed TCP connection needs
// to be closed on our side too.
data_socket_.reset();
// No more data so send QUIT Command now and wait for response.
return Stop(OK);
}
next_state_ = STATE_DATA_READ_COMPLETE;
read_data_buf_->data()[0] = 0;
return data_socket_->Read(read_data_buf_, read_data_buf_len_,
&io_callback_);
}
int FtpNetworkTransaction::DoDataReadComplete(int result) {
return result;
}
// We're using a histogram as a group of counters, with one bucket for each
// enumeration value. We're only interested in the values of the counters.
// Ignore the shape, average, and standard deviation of the histograms because
// they are meaningless.
//
// We use two histograms. In the first histogram we tally whether the user has
// seen an error of that type during the session. In the second histogram we
// tally the total number of times the users sees each errer.
void FtpNetworkTransaction::RecordDataConnectionError(int result) {
// Gather data for http://crbug.com/3073. See how many users have trouble
// establishing FTP data connection in passive FTP mode.
enum {
// Data connection successful.
NET_ERROR_OK = 0,
// Local firewall blocked the connection.
NET_ERROR_ACCESS_DENIED = 1,
// Connection timed out.
NET_ERROR_TIMED_OUT = 2,
// Connection has been estabilished, but then got broken (either reset
// or aborted).
NET_ERROR_CONNECTION_BROKEN = 3,
// Connection has been refused.
NET_ERROR_CONNECTION_REFUSED = 4,
// No connection to the internet.
NET_ERROR_INTERNET_DISCONNECTED = 5,
// Could not reach the destination address.
NET_ERROR_ADDRESS_UNREACHABLE = 6,
// A programming error in our network stack.
NET_ERROR_UNEXPECTED = 7,
// Other kind of error.
NET_ERROR_OTHER = 20,
NUM_OF_NET_ERROR_TYPES
} type;
switch (result) {
case OK:
type = NET_ERROR_OK;
break;
case ERR_ACCESS_DENIED:
type = NET_ERROR_ACCESS_DENIED;
break;
case ERR_TIMED_OUT:
type = NET_ERROR_TIMED_OUT;
break;
case ERR_CONNECTION_ABORTED:
case ERR_CONNECTION_RESET:
case ERR_CONNECTION_CLOSED:
type = NET_ERROR_CONNECTION_BROKEN;
break;
case ERR_CONNECTION_FAILED:
case ERR_CONNECTION_REFUSED:
type = NET_ERROR_CONNECTION_REFUSED;
break;
case ERR_INTERNET_DISCONNECTED:
type = NET_ERROR_INTERNET_DISCONNECTED;
break;
case ERR_ADDRESS_INVALID:
case ERR_ADDRESS_UNREACHABLE:
type = NET_ERROR_ADDRESS_UNREACHABLE;
break;
case ERR_UNEXPECTED:
type = NET_ERROR_UNEXPECTED;
break;
default:
type = NET_ERROR_OTHER;
break;
};
static bool had_error_type[NUM_OF_NET_ERROR_TYPES];
DCHECK(type >= 0 && type < NUM_OF_NET_ERROR_TYPES);
if (!had_error_type[type]) {
had_error_type[type] = true;
UMA_HISTOGRAM_ENUMERATION("Net.FtpDataConnectionErrorHappened",
type, NUM_OF_NET_ERROR_TYPES);
}
UMA_HISTOGRAM_ENUMERATION("Net.FtpDataConnectionErrorCount",
type, NUM_OF_NET_ERROR_TYPES);
}
} // namespace net