src/servers/FtpServer.cc

   1 /*
   2  * Copyright (C) 1996-2014 The Squid Software Foundation and contributors
   3  *
   4  * Squid software is distributed under GPLv2+ license and includes
   5  * contributions from numerous individuals and organizations.
   6  * Please see the COPYING and CONTRIBUTORS files for details.
   7  */
   8
   9 /* DEBUG: section 33    Transfer protocol servers */
  10
  11 #include "squid.h"
  12 #include "acl/FilledChecklist.h"
  13 #include "base/CharacterSet.h"
  14 #include "base/RefCount.h"
  15 #include "base/Subscription.h"
  16 #include "client_side_reply.h"
  17 #include "client_side_request.h"
  18 #include "clientStream.h"
  19 #include "comm/ConnOpener.h"
  20 #include "comm/Read.h"
  21 #include "comm/TcpAcceptor.h"
  22 #include "comm/Write.h"
  23 #include "errorpage.h"
  24 #include "fd.h"
  25 #include "ftp/Elements.h"
  26 #include "ftp/Parsing.h"
  27 #include "globals.h"
  28 #include "http/one/RequestParser.h"
  29 #include "HttpHdrCc.h"
  30 #include "ip/tools.h"
  31 #include "ipc/FdNotes.h"
  32 #include "parser/Tokenizer.h"
  33 #include "servers/forward.h"
  34 #include "servers/FtpServer.h"
  35 #include "SquidConfig.h"
  36 #include "StatCounters.h"
  37 #include "tools.h"
  38
  39 #include <set>
  40 #include <map>
  41
  42 CBDATA_NAMESPACED_CLASS_INIT(Ftp, Server);
  43
  44 namespace Ftp
  45 {
  46 static void PrintReply(MemBuf &mb, const HttpReply *reply, const char *const prefix = "");
  47 static bool SupportedCommand(const SBuf &name);
  48 static bool CommandHasPathParameter(const SBuf &cmd);
  49 };
  50
  51 Ftp::Server::Server(const MasterXaction::Pointer &xact):
  52     AsyncJob("Ftp::Server"),
  53     ConnStateData(xact),
  54     master(new MasterState),
  55     uri(),
  56     host(),
  57     gotEpsvAll(false),
  58     onDataAcceptCall(),
  59     dataListenConn(),
  60     dataConn(),
  61     uploadAvailSize(0),
  62     listener(),
  63     connector(),
  64     reader()
  65 {
  66     flags.readMore = false; // we need to announce ourselves first
  67     *uploadBuf = 0;
  68 }
  69
  70 Ftp::Server::~Server()
  71 {
  72     closeDataConnection();
  73 }
  74
  75 int
  76 Ftp::Server::pipelinePrefetchMax() const
  77 {
  78     return 0; // no support for concurrent FTP requests
  79 }
  80
  81 time_t
  82 Ftp::Server::idleTimeout() const
  83 {
  84     return Config.Timeout.ftpClientIdle;
  85 }
  86
  87 void
  88 Ftp::Server::start()
  89 {
  90     ConnStateData::start();
  91
  92     if (transparent()) {
  93         char buf[MAX_IPSTRLEN];
  94         clientConnection->local.toUrl(buf, MAX_IPSTRLEN);
  95         host = buf;
  96         calcUri(NULL);
  97         debugs(33, 5, "FTP transparent URL: " << uri);
  98     }
  99
 100     writeEarlyReply(220, "Service ready");
 101 }
 102
 103 /// schedules another data connection read if needed
 104 void
 105 Ftp::Server::maybeReadUploadData()
 106 {
 107     if (reader != NULL)
 108         return;
 109
 110     const size_t availSpace = sizeof(uploadBuf) - uploadAvailSize;
 111     if (availSpace <= 0)
 112         return;
 113
 114     debugs(33, 4, dataConn << ": reading FTP data...");
 115
 116     typedef CommCbMemFunT<Server, CommIoCbParams> Dialer;
 117     reader = JobCallback(33, 5, Dialer, this, Ftp::Server::readUploadData);
 118     comm_read(dataConn, uploadBuf + uploadAvailSize, availSpace,
 119               reader);
 120 }
 121
 122 /// react to the freshly parsed request
 123 void
 124 Ftp::Server::doProcessRequest()
 125 {
 126     // zero pipelinePrefetchMax() ensures that there is only parsed request
 127     ClientSocketContext::Pointer context = getCurrentContext();
 128     Must(context != NULL);
 129     Must(getConcurrentRequestCount() == 1);
 130
 131     ClientHttpRequest *const http = context->http;
 132     assert(http != NULL);
 133
 134     HttpRequest *const request = http->request;
 135     Must(http->storeEntry() || request);
 136     const bool mayForward = !http->storeEntry() && handleRequest(request);
 137
 138     if (http->storeEntry() != NULL) {
 139         debugs(33, 4, "got an immediate response");
 140         clientSetKeepaliveFlag(http);
 141         context->pullData();
 142     } else if (mayForward) {
 143         debugs(33, 4, "forwarding request to server side");
 144         assert(http->storeEntry() == NULL);
 145         clientProcessRequest(this, Http1::RequestParserPointer(), context.getRaw());
 146     } else {
 147         debugs(33, 4, "will resume processing later");
 148     }
 149 }
 150
 151 void
 152 Ftp::Server::processParsedRequest(ClientSocketContext *context)
 153 {
 154     Must(getConcurrentRequestCount() == 1);
 155
 156     // Process FTP request asynchronously to make sure FTP
 157     // data connection accept callback is fired first.
 158     CallJobHere(33, 4, CbcPointer<Server>(this),
 159                 Ftp::Server, doProcessRequest);
 160 }
 161
 162 /// imports more upload data from the data connection
 163 void
 164 Ftp::Server::readUploadData(const CommIoCbParams &io)
 165 {
 166     debugs(33, 5, io.conn << " size " << io.size);
 167     Must(reader != NULL);
 168     reader = NULL;
 169
 170     assert(Comm::IsConnOpen(dataConn));
 171     assert(io.conn->fd == dataConn->fd);
 172
 173     if (io.flag == Comm::OK && bodyPipe != NULL) {
 174         if (io.size > 0) {
 175             kb_incr(&(statCounter.client_http.kbytes_in), io.size);
 176
 177             char *const current_buf = uploadBuf + uploadAvailSize;
 178             if (io.buf != current_buf)
 179                 memmove(current_buf, io.buf, io.size);
 180             uploadAvailSize += io.size;
 181             shovelUploadData();
 182         } else if (io.size == 0) {
 183             debugs(33, 5, io.conn << " closed");
 184             closeDataConnection();
 185             if (uploadAvailSize <= 0)
 186                 finishDechunkingRequest(true);
 187         }
 188     } else { // not Comm::Flags::OK or unexpected read
 189         debugs(33, 5, io.conn << " closed");
 190         closeDataConnection();
 191         finishDechunkingRequest(false);
 192     }
 193
 194 }
 195
 196 /// shovel upload data from the internal buffer to the body pipe if possible
 197 void
 198 Ftp::Server::shovelUploadData()
 199 {
 200     assert(bodyPipe != NULL);
 201
 202     debugs(33, 5, "handling FTP request data for " << clientConnection);
 203     const size_t putSize = bodyPipe->putMoreData(uploadBuf,
 204                            uploadAvailSize);
 205     if (putSize > 0) {
 206         uploadAvailSize -= putSize;
 207         if (uploadAvailSize > 0)
 208             memmove(uploadBuf, uploadBuf + putSize, uploadAvailSize);
 209     }
 210
 211     if (Comm::IsConnOpen(dataConn))
 212         maybeReadUploadData();
 213     else if (uploadAvailSize <= 0)
 214         finishDechunkingRequest(true);
 215 }
 216
 217 void
 218 Ftp::Server::noteMoreBodySpaceAvailable(BodyPipe::Pointer)
 219 {
 220     shovelUploadData();
 221 }
 222
 223 void
 224 Ftp::Server::noteBodyConsumerAborted(BodyPipe::Pointer ptr)
 225 {
 226     ConnStateData::noteBodyConsumerAborted(ptr);
 227     closeDataConnection();
 228 }
 229
 230 /// accept a new FTP control connection and hand it to a dedicated Server
 231 void
 232 Ftp::Server::AcceptCtrlConnection(const CommAcceptCbParams &params)
 233 {
 234     MasterXaction::Pointer xact = params.xaction;
 235     AnyP::PortCfgPointer s = xact->squidPort;
 236
 237     // NP: it is possible the port was reconfigured when the call or accept() was queued.
 238
 239     if (params.flag != Comm::OK) {
 240         // Its possible the call was still queued when the client disconnected
 241         debugs(33, 2, s->listenConn << ": FTP accept failure: " << xstrerr(params.xerrno));
 242         return;
 243     }
 244
 245     debugs(33, 4, params.conn << ": accepted");
 246     fd_note(params.conn->fd, "client ftp connect");
 247
 248     if (s->tcp_keepalive.enabled)
 249         commSetTcpKeepalive(params.conn->fd, s->tcp_keepalive.idle, s->tcp_keepalive.interval, s->tcp_keepalive.timeout);
 250
 251     ++incoming_sockets_accepted;
 252
 253     AsyncJob::Start(new Server(xact));
 254 }
 255
 256 void
 257 Ftp::StartListening()
 258 {
 259     for (AnyP::PortCfgPointer s = FtpPortList; s != NULL; s = s->next) {
 260         if (MAXTCPLISTENPORTS == NHttpSockets) {
 261             debugs(1, DBG_IMPORTANT, "Ignoring ftp_port lines exceeding the" <<
 262                    " limit of " << MAXTCPLISTENPORTS << " ports.");
 263             break;
 264         }
 265
 266         // direct new connections accepted by listenConn to Accept()
 267         typedef CommCbFunPtrCallT<CommAcceptCbPtrFun> AcceptCall;
 268         RefCount<AcceptCall> subCall = commCbCall(5, 5, "Ftp::Server::AcceptCtrlConnection",
 269                                        CommAcceptCbPtrFun(Ftp::Server::AcceptCtrlConnection,
 270                                                CommAcceptCbParams(NULL)));
 271         clientStartListeningOn(s, subCall, Ipc::fdnFtpSocket);
 272     }
 273 }
 274
 275 void
 276 Ftp::StopListening()
 277 {
 278     for (AnyP::PortCfgPointer s = FtpPortList; s != NULL; s = s->next) {
 279         if (s->listenConn != NULL) {
 280             debugs(1, DBG_IMPORTANT, "Closing FTP port " << s->listenConn->local);
 281             s->listenConn->close();
 282             s->listenConn = NULL;
 283         }
 284     }
 285 }
 286
 287 void
 288 Ftp::Server::notePeerConnection(Comm::ConnectionPointer conn)
 289 {
 290     // find request
 291     ClientSocketContext::Pointer context = getCurrentContext();
 292     Must(context != NULL);
 293     ClientHttpRequest *const http = context->http;
 294     Must(http != NULL);
 295     HttpRequest *const request = http->request;
 296     Must(request != NULL);
 297
 298     // this is not an idle connection, so we do not want I/O monitoring
 299     const bool monitor = false;
 300
 301     // make FTP peer connection exclusive to our request
 302     pinConnection(conn, request, conn->getPeer(), false, monitor);
 303 }
 304
 305 void
 306 Ftp::Server::clientPinnedConnectionClosed(const CommCloseCbParams &io)
 307 {
 308     ConnStateData::clientPinnedConnectionClosed(io);
 309
 310     // if the server control connection is gone, reset state to login again
 311     resetLogin("control connection closure");
 312
 313     // XXX: Reseting is not enough. FtpRelay::sendCommand() will not re-login
 314     // because FtpRelay::serverState() is not going to be fssConnected.
 315 }
 316
 317 /// clear client and server login-related state after the old login is gone
 318 void
 319 Ftp::Server::resetLogin(const char *reason)
 320 {
 321     debugs(33, 5, "will need to re-login due to " << reason);
 322     master->clientReadGreeting = false;
 323     changeState(fssBegin, reason);
 324 }
 325
 326 /// computes uri member from host and, if tracked, working dir with file name
 327 void
 328 Ftp::Server::calcUri(const SBuf *file)
 329 {
 330     uri = "ftp://";
 331     uri.append(host);
 332     if (port->ftp_track_dirs && master->workingDir.length()) {
 333         if (master->workingDir[0] != '/')
 334             uri.append("/");
 335         uri.append(master->workingDir);
 336     }
 337
 338     if (uri[uri.length() - 1] != '/')
 339         uri.append("/");
 340
 341     if (port->ftp_track_dirs && file) {
 342         static const CharacterSet Slash("/", "/");
 343         Parser::Tokenizer tok(*file);
 344         tok.skipAll(Slash);
 345         uri.append(tok.remaining());
 346     }
 347 }
 348
 349 /// Starts waiting for a data connection. Returns listening port.
 350 /// On errors, responds with an error and returns zero.
 351 unsigned int
 352 Ftp::Server::listenForDataConnection()
 353 {
 354     closeDataConnection();
 355
 356     Comm::ConnectionPointer conn = new Comm::Connection;
 357     conn->flags = COMM_NONBLOCKING;
 358     conn->local = transparent() ? port->s : clientConnection->local;
 359     conn->local.port(0);
 360     const char *const note = uri.c_str();
 361     comm_open_listener(SOCK_STREAM, IPPROTO_TCP, conn, note);
 362     if (!Comm::IsConnOpen(conn)) {
 363         debugs(5, DBG_CRITICAL, "comm_open_listener failed for FTP data: " <<
 364                conn->local << " error: " << errno);
 365         writeCustomReply(451, "Internal error");
 366         return 0;
 367     }
 368
 369     typedef CommCbMemFunT<Server, CommAcceptCbParams> AcceptDialer;
 370     typedef AsyncCallT<AcceptDialer> AcceptCall;
 371     RefCount<AcceptCall> call = static_cast<AcceptCall*>(JobCallback(5, 5, AcceptDialer, this, Ftp::Server::acceptDataConnection));
 372     Subscription::Pointer sub = new CallSubscription<AcceptCall>(call);
 373     listener = call.getRaw();
 374     dataListenConn = conn;
 375     AsyncJob::Start(new Comm::TcpAcceptor(conn, note, sub));
 376
 377     const unsigned int listeningPort = comm_local_port(conn->fd);
 378     conn->local.port(listeningPort);
 379     return listeningPort;
 380 }
 381
 382 void
 383 Ftp::Server::acceptDataConnection(const CommAcceptCbParams &params)
 384 {
 385     if (params.flag != Comm::OK) {
 386         // Its possible the call was still queued when the client disconnected
 387         debugs(33, 2, dataListenConn << ": accept "
 388                "failure: " << xstrerr(params.xerrno));
 389         return;
 390     }
 391
 392     debugs(33, 4, "accepted " << params.conn);
 393     fd_note(params.conn->fd, "passive client ftp data");
 394     ++incoming_sockets_accepted;
 395
 396     if (!clientConnection) {
 397         debugs(33, 5, "late data connection?");
 398         closeDataConnection(); // in case we are still listening
 399         params.conn->close();
 400     } else if (params.conn->remote != clientConnection->remote) {
 401         debugs(33, 2, "rogue data conn? ctrl: " << clientConnection->remote);
 402         params.conn->close();
 403         // Some FTP servers close control connection here, but it may make
 404         // things worse from DoS p.o.v. and no better from data stealing p.o.v.
 405     } else {
 406         closeDataConnection();
 407         dataConn = params.conn;
 408         uploadAvailSize = 0;
 409         debugs(33, 7, "ready for data");
 410         if (onDataAcceptCall != NULL) {
 411             AsyncCall::Pointer call = onDataAcceptCall;
 412             onDataAcceptCall = NULL;
 413             // If we got an upload request, start reading data from the client.
 414             if (master->serverState == fssHandleUploadRequest)
 415                 maybeReadUploadData();
 416             else
 417                 Must(master->serverState == fssHandleDataRequest);
 418             MemBuf mb;
 419             mb.init();
 420             mb.Printf("150 Data connection opened.\r\n");
 421             Comm::Write(clientConnection, &mb, call);
 422         }
 423     }
 424 }
 425
 426 void
 427 Ftp::Server::closeDataConnection()
 428 {
 429     if (listener != NULL) {
 430         listener->cancel("no longer needed");
 431         listener = NULL;
 432     }
 433
 434     if (Comm::IsConnOpen(dataListenConn)) {
 435         debugs(33, 5, "FTP closing client data listen socket: " <<
 436                *dataListenConn);
 437         dataListenConn->close();
 438     }
 439     dataListenConn = NULL;
 440
 441     if (reader != NULL) {
 442         // Comm::ReadCancel can deal with negative FDs
 443         Comm::ReadCancel(dataConn->fd, reader);
 444         reader = NULL;
 445     }
 446
 447     if (Comm::IsConnOpen(dataConn)) {
 448         debugs(33, 5, "FTP closing client data connection: " <<
 449                *dataConn);
 450         dataConn->close();
 451     }
 452     dataConn = NULL;
 453 }
 454
 455 /// Writes FTP [error] response before we fully parsed the FTP request and
 456 /// created the corresponding HTTP request wrapper for that FTP request.
 457 void
 458 Ftp::Server::writeEarlyReply(const int code, const char *msg)
 459 {
 460     debugs(33, 7, code << ' ' << msg);
 461     assert(99 < code && code < 1000);
 462
 463     MemBuf mb;
 464     mb.init();
 465     mb.Printf("%i %s\r\n", code, msg);
 466
 467     typedef CommCbMemFunT<Server, CommIoCbParams> Dialer;
 468     AsyncCall::Pointer call = JobCallback(33, 5, Dialer, this, Ftp::Server::wroteEarlyReply);
 469     Comm::Write(clientConnection, &mb, call);
 470
 471     flags.readMore = false;
 472
 473     // TODO: Create master transaction. Log it in wroteEarlyReply().
 474 }
 475
 476 void
 477 Ftp::Server::writeReply(MemBuf &mb)
 478 {
 479     debugs(9, 2, "FTP Client " << clientConnection);
 480     debugs(9, 2, "FTP Client REPLY:\n---------\n" << mb.buf <<
 481            "\n----------");
 482
 483     typedef CommCbMemFunT<Server, CommIoCbParams> Dialer;
 484     AsyncCall::Pointer call = JobCallback(33, 5, Dialer, this, Ftp::Server::wroteReply);
 485     Comm::Write(clientConnection, &mb, call);
 486 }
 487
 488 void
 489 Ftp::Server::writeCustomReply(const int code, const char *msg, const HttpReply *reply)
 490 {
 491     debugs(33, 7, code << ' ' << msg);
 492     assert(99 < code && code < 1000);
 493
 494     const bool sendDetails = reply != NULL &&
 495                              reply->header.has(HDR_FTP_STATUS) && reply->header.has(HDR_FTP_REASON);
 496
 497     MemBuf mb;
 498     mb.init();
 499     if (sendDetails) {
 500         mb.Printf("%i-%s\r\n", code, msg);
 501         mb.Printf(" Server reply:\r\n");
 502         Ftp::PrintReply(mb, reply, " ");
 503         mb.Printf("%i \r\n", code);
 504     } else
 505         mb.Printf("%i %s\r\n", code, msg);
 506
 507     writeReply(mb);
 508 }
 509
 510 void
 511 Ftp::Server::changeState(const ServerState newState, const char *reason)
 512 {
 513     if (master->serverState == newState) {
 514         debugs(33, 3, "client state unchanged at " << master->serverState <<
 515                " because " << reason);
 516         master->serverState = newState;
 517     } else {
 518         debugs(33, 3, "client state was " << master->serverState <<
 519                ", now " << newState << " because " << reason);
 520         master->serverState = newState;
 521     }
 522 }
 523
 524 /// whether the given FTP command has a pathname parameter
 525 static bool
 526 Ftp::CommandHasPathParameter(const SBuf &cmd)
 527 {
 528     static std::set<SBuf> PathedCommands;
 529     if (!PathedCommands.size()) {
 530         PathedCommands.insert(cmdMlst());
 531         PathedCommands.insert(cmdMlsd());
 532         PathedCommands.insert(cmdStat());
 533         PathedCommands.insert(cmdNlst());
 534         PathedCommands.insert(cmdList());
 535         PathedCommands.insert(cmdMkd());
 536         PathedCommands.insert(cmdRmd());
 537         PathedCommands.insert(cmdDele());
 538         PathedCommands.insert(cmdRnto());
 539         PathedCommands.insert(cmdRnfr());
 540         PathedCommands.insert(cmdAppe());
 541         PathedCommands.insert(cmdStor());
 542         PathedCommands.insert(cmdRetr());
 543         PathedCommands.insert(cmdSmnt());
 544         PathedCommands.insert(cmdCwd());
 545     }
 546
 547     return PathedCommands.find(cmd) != PathedCommands.end();
 548 }
 549
 550 /// creates a context filled with an error message for a given early error
 551 ClientSocketContext *
 552 Ftp::Server::earlyError(const EarlyErrorKind eek)
 553 {
 554     /* Default values, to be updated by the switch statement below */
 555     int scode = 421;
 556     const char *reason = "Internal error";
 557     const char *errUri = "error:ftp-internal-early-error";
 558
 559     switch (eek) {
 560     case eekHugeRequest:
 561         scode = 421;
 562         reason = "Huge request";
 563         errUri = "error:ftp-huge-request";
 564         break;
 565
 566     case eekMissingLogin:
 567         scode = 530;
 568         reason = "Must login first";
 569         errUri = "error:ftp-must-login-first";
 570         break;
 571
 572     case eekMissingUsername:
 573         scode = 501;
 574         reason = "Missing username";
 575         errUri = "error:ftp-missing-username";
 576         break;
 577
 578     case eekMissingHost:
 579         scode = 501;
 580         reason = "Missing host";
 581         errUri = "error:ftp-missing-host";
 582         break;
 583
 584     case eekUnsupportedCommand:
 585         scode = 502;
 586         reason = "Unknown or unsupported command";
 587         errUri = "error:ftp-unsupported-command";
 588         break;
 589
 590     case eekInvalidUri:
 591         scode = 501;
 592         reason = "Invalid URI";
 593         errUri = "error:ftp-invalid-uri";
 594         break;
 595
 596     case eekMalformedCommand:
 597         scode = 421;
 598         reason = "Malformed command";
 599         errUri = "error:ftp-malformed-command";
 600         break;
 601
 602         // no default so that a compiler can check that we have covered all cases
 603     }
 604
 605     ClientSocketContext *context = abortRequestParsing(errUri);
 606     clientStreamNode *node = context->getClientReplyContext();
 607     Must(node);
 608     clientReplyContext *repContext = dynamic_cast<clientReplyContext *>(node->data.getRaw());
 609     Must(repContext);
 610
 611     // We cannot relay FTP scode/reason via HTTP-specific ErrorState.
 612     // TODO: When/if ErrorState can handle native FTP errors, use it instead.
 613     HttpReply *reply = Ftp::HttpReplyWrapper(scode, reason, Http::scBadRequest, -1);
 614     repContext->setReplyToReply(reply);
 615     return context;
 616 }
 617
 618 /// Parses a single FTP request on the control connection.
 619 /// Returns a new ClientSocketContext on valid requests and all errors.
 620 /// Returns NULL on incomplete requests that may still succeed given more data.
 621 ClientSocketContext *
 622 Ftp::Server::parseOneRequest()
 623 {
 624     flags.readMore = false; // common for all but one case below
 625
 626     // OWS <command> [ RWS <parameter> ] OWS LF
 627
 628     // InlineSpaceChars are isspace(3) or RFC 959 Section 3.1.1.5.2, except
 629     // for the LF character that we must exclude here (but see FullWhiteSpace).
 630     static const char * const InlineSpaceChars = " \f\r\t\v";
 631     static const CharacterSet InlineSpace = CharacterSet("Ftp::Inline", InlineSpaceChars);
 632     static const CharacterSet FullWhiteSpace = (InlineSpace + CharacterSet::LF).rename("Ftp::FWS");
 633     static const CharacterSet CommandChars = FullWhiteSpace.complement("Ftp::Command");
 634     static const CharacterSet TailChars = CharacterSet::LF.complement("Ftp::Tail");
 635
 636     // This set is used to ignore empty commands without allowing an attacker
 637     // to keep us endlessly busy by feeding us whitespace or empty commands.
 638     static const CharacterSet &LeadingSpace = FullWhiteSpace;
 639
 640     SBuf cmd;
 641     SBuf params;
 642
 643     Parser::Tokenizer tok(in.buf);
 644
 645     (void)tok.skipAll(LeadingSpace); // leading OWS and empty commands
 646     const bool parsed = tok.prefix(cmd, CommandChars); // required command
 647
 648     // note that the condition below will eat either RWS or trailing OWS
 649     if (parsed && tok.skipAll(InlineSpace) && tok.prefix(params, TailChars)) {
 650         // now params may include trailing OWS
 651         // TODO: Support right-trimming using CharacterSet in Tokenizer instead
 652         static const SBuf bufWhiteSpace(InlineSpaceChars);
 653         params.trim(bufWhiteSpace, false, true);
 654     }
 655
 656     // Why limit command line and parameters size? Did not we just parse them?
 657     // XXX: Our good old String cannot handle very long strings.
 658     const SBuf::size_type tokenMax = min(
 659                                          static_cast<SBuf::size_type>(32*1024), // conservative
 660                                          static_cast<SBuf::size_type>(Config.maxRequestHeaderSize));
 661     if (cmd.length() > tokenMax || params.length() > tokenMax) {
 662         changeState(fssError, "huge req token");
 663         quitAfterError(NULL);
 664         return earlyError(eekHugeRequest);
 665     }
 666
 667     // technically, we may skip multiple NLs below, but that is OK
 668     if (!parsed || !tok.skipAll(CharacterSet::LF)) { // did not find terminating LF yet
 669         // we need more data, but can we buffer more?
 670         if (in.buf.length() >= Config.maxRequestHeaderSize) {
 671             changeState(fssError, "huge req");
 672             quitAfterError(NULL);
 673             return earlyError(eekHugeRequest);
 674         } else {
 675             flags.readMore = true;
 676             debugs(33, 5, "Waiting for more, up to " <<
 677                    (Config.maxRequestHeaderSize - in.buf.length()));
 678             return NULL;
 679         }
 680     }
 681
 682     Must(parsed && cmd.length());
 683     consumeInput(tok.parsedSize()); // TODO: Would delaying optimize copying?
 684
 685     debugs(33, 2, ">>ftp " << cmd << (params.isEmpty() ? "" : " ") << params);
 686
 687     cmd.toUpper(); // this should speed up and simplify future comparisons
 688
 689     // interception cases do not need USER to calculate the uri
 690     if (!transparent()) {
 691         if (!master->clientReadGreeting) {
 692             // the first command must be USER
 693             if (!pinning.pinned && cmd != cmdUser())
 694                 return earlyError(eekMissingLogin);
 695         }
 696
 697         // process USER request now because it sets FTP peer host name
 698         if (cmd == cmdUser()) {
 699             if (ClientSocketContext *errCtx = handleUserRequest(cmd, params))
 700                 return errCtx;
 701         }
 702     }
 703
 704     if (!Ftp::SupportedCommand(cmd))
 705         return earlyError(eekUnsupportedCommand);
 706
 707     const HttpRequestMethod method =
 708         cmd == cmdAppe() || cmd == cmdStor() || cmd == cmdStou() ?
 709         Http::METHOD_PUT : Http::METHOD_GET;
 710
 711     const SBuf *path = (params.length() && CommandHasPathParameter(cmd)) ?
 712                        &params : NULL;
 713     calcUri(path);
 714     char *newUri = xstrdup(uri.c_str());
 715     HttpRequest *const request = HttpRequest::CreateFromUrlAndMethod(newUri, method);
 716     if (!request) {
 717         debugs(33, 5, "Invalid FTP URL: " << uri);
 718         uri.clear();
 719         safe_free(newUri);
 720         return earlyError(eekInvalidUri);
 721     }
 722
 723     request->flags.ftpNative = true;
 724     request->http_ver = Http::ProtocolVersion(Ftp::ProtocolVersion().major, Ftp::ProtocolVersion().minor);
 725
 726     // Our fake Request-URIs are not distinctive enough for caching to work
 727     request->flags.cachable = false; // XXX: reset later by maybeCacheable()
 728     request->flags.noCache = true;
 729
 730     request->header.putStr(HDR_FTP_COMMAND, cmd.c_str());
 731     request->header.putStr(HDR_FTP_ARGUMENTS, params.c_str()); // may be ""
 732     if (method == Http::METHOD_PUT) {
 733         request->header.putStr(HDR_EXPECT, "100-continue");
 734         request->header.putStr(HDR_TRANSFER_ENCODING, "chunked");
 735     }
 736
 737     ClientHttpRequest *const http = new ClientHttpRequest(this);
 738     http->request = request;
 739     HTTPMSGLOCK(http->request);
 740     http->req_sz = tok.parsedSize();
 741     http->uri = newUri;
 742
 743     ClientSocketContext *const result =
 744         new ClientSocketContext(clientConnection, http);
 745
 746     StoreIOBuffer tempBuffer;
 747     tempBuffer.data = result->reqbuf;
 748     tempBuffer.length = HTTP_REQBUF_SZ;
 749
 750     ClientStreamData newServer = new clientReplyContext(http);
 751     ClientStreamData newClient = result;
 752     clientStreamInit(&http->client_stream, clientGetMoreData, clientReplyDetach,
 753                      clientReplyStatus, newServer, clientSocketRecipient,
 754                      clientSocketDetach, newClient, tempBuffer);
 755
 756     result->flags.parsed_ok = 1;
 757     return result;
 758 }
 759
 760 void
 761 Ftp::Server::handleReply(HttpReply *reply, StoreIOBuffer data)
 762 {
 763     // the caller guarantees that we are dealing with the current context only
 764     ClientSocketContext::Pointer context = getCurrentContext();
 765     assert(context != NULL);
 766
 767     if (context->http && context->http->al != NULL &&
 768             !context->http->al->reply && reply) {
 769         context->http->al->reply = reply;
 770         HTTPMSGLOCK(context->http->al->reply);
 771     }
 772
 773     static ReplyHandler handlers[] = {
 774         NULL, // fssBegin
 775         NULL, // fssConnected
 776         &Ftp::Server::handleFeatReply, // fssHandleFeat
 777         &Ftp::Server::handlePasvReply, // fssHandlePasv
 778         &Ftp::Server::handlePortReply, // fssHandlePort
 779         &Ftp::Server::handleDataReply, // fssHandleDataRequest
 780         &Ftp::Server::handleUploadReply, // fssHandleUploadRequest
 781         &Ftp::Server::handleEprtReply,// fssHandleEprt
 782         &Ftp::Server::handleEpsvReply,// fssHandleEpsv
 783         NULL, // fssHandleCwd
 784         NULL, // fssHandlePass
 785         NULL, // fssHandleCdup
 786         &Ftp::Server::handleErrorReply // fssError
 787     };
 788     const Server &server = dynamic_cast<const Ftp::Server&>(*context->getConn());
 789     if (const ReplyHandler handler = handlers[server.master->serverState])
 790         (this->*handler)(reply, data);
 791     else
 792         writeForwardedReply(reply);
 793 }
 794
 795 void
 796 Ftp::Server::handleFeatReply(const HttpReply *reply, StoreIOBuffer)
 797 {
 798     if (getCurrentContext()->http->request->errType != ERR_NONE) {
 799         writeCustomReply(502, "Server does not support FEAT", reply);
 800         return;
 801     }
 802
 803     HttpReply::Pointer featReply = Ftp::HttpReplyWrapper(211, "End", Http::scNoContent, 0);
 804     HttpHeader const &serverReplyHeader = reply->header;
 805
 806     HttpHeaderPos pos = HttpHeaderInitPos;
 807     bool hasEPRT = false;
 808     bool hasEPSV = false;
 809     int prependSpaces = 1;
 810
 811     featReply->header.putStr(HDR_FTP_PRE, "\"211-Features:\"");
 812     const int scode = serverReplyHeader.getInt(HDR_FTP_STATUS);
 813     if (scode == 211) {
 814         while (const HttpHeaderEntry *e = serverReplyHeader.getEntry(&pos)) {
 815             if (e->id == HDR_FTP_PRE) {
 816                 // assume RFC 2389 FEAT response format, quoted by Squid:
 817                 // <"> SP NAME [SP PARAMS] <">
 818                 // but accommodate MS servers sending four SPs before NAME
 819
 820                 // command name ends with (SP parameter) or quote
 821                 static const CharacterSet AfterFeatNameChars("AfterFeatName", " \"");
 822                 static const CharacterSet FeatNameChars = AfterFeatNameChars.complement("FeatName");
 823
 824                 Parser::Tokenizer tok(SBuf(e->value.termedBuf()));
 825                 if (!tok.skip('"') || !tok.skip(' '))
 826                     continue;
 827
 828                 // optional spaces; remember their number to accomodate MS servers
 829                 prependSpaces = 1 + tok.skipAll(CharacterSet::SP);
 830
 831                 SBuf cmd;
 832                 if (!tok.prefix(cmd, FeatNameChars))
 833                     continue;
 834                 cmd.toUpper();
 835
 836                 if (Ftp::SupportedCommand(cmd)) {
 837                     featReply->header.addEntry(e->clone());
 838                 }
 839
 840                 if (cmd == cmdEprt())
 841                     hasEPRT = true;
 842                 else if (cmd == cmdEpsv())
 843                     hasEPSV = true;
 844             }
 845         }
 846     } // else we got a FEAT error and will only report Squid-supported features
 847
 848     char buf[256];
 849     if (!hasEPRT) {
 850         snprintf(buf, sizeof(buf), "\"%*s\"", prependSpaces + 4, "EPRT");
 851         featReply->header.putStr(HDR_FTP_PRE, buf);
 852     }
 853     if (!hasEPSV) {
 854         snprintf(buf, sizeof(buf), "\"%*s\"", prependSpaces + 4, "EPSV");
 855         featReply->header.putStr(HDR_FTP_PRE, buf);
 856     }
 857
 858     featReply->header.refreshMask();
 859
 860     writeForwardedReply(featReply.getRaw());
 861 }
 862
 863 void
 864 Ftp::Server::handlePasvReply(const HttpReply *reply, StoreIOBuffer)
 865 {
 866     ClientSocketContext::Pointer context = getCurrentContext();
 867     assert(context != NULL);
 868
 869     if (context->http->request->errType != ERR_NONE) {
 870         writeCustomReply(502, "Server does not support PASV", reply);
 871         return;
 872     }
 873
 874     const unsigned short localPort = listenForDataConnection();
 875     if (!localPort)
 876         return;
 877
 878     char addr[MAX_IPSTRLEN];
 879     // remote server in interception setups and local address otherwise
 880     const Ip::Address &server = transparent() ?
 881                                 clientConnection->local : dataListenConn->local;
 882     server.toStr(addr, MAX_IPSTRLEN, AF_INET);
 883     addr[MAX_IPSTRLEN - 1] = '\0';
 884     for (char *c = addr; *c != '\0'; ++c) {
 885         if (*c == '.')
 886             *c = ',';
 887     }
 888
 889     // In interception setups, we combine remote server address with a
 890     // local port number and hope that traffic will be redirected to us.
 891     // Do not use "227 =a,b,c,d,p1,p2" format or omit parens: some nf_ct_ftp
 892     // versions block responses that use those alternative syntax rules!
 893     MemBuf mb;
 894     mb.init();
 895     mb.Printf("227 Entering Passive Mode (%s,%i,%i).\r\n",
 896               addr,
 897               static_cast<int>(localPort / 256),
 898               static_cast<int>(localPort % 256));
 899     debugs(9, 3, Raw("writing", mb.buf, mb.size));
 900     writeReply(mb);
 901 }
 902
 903 void
 904 Ftp::Server::handlePortReply(const HttpReply *reply, StoreIOBuffer)
 905 {
 906     if (getCurrentContext()->http->request->errType != ERR_NONE) {
 907         writeCustomReply(502, "Server does not support PASV (converted from PORT)", reply);
 908         return;
 909     }
 910
 911     writeCustomReply(200, "PORT successfully converted to PASV.");
 912
 913     // and wait for RETR
 914 }
 915
 916 void
 917 Ftp::Server::handleErrorReply(const HttpReply *reply, StoreIOBuffer)
 918 {
 919     if (!pinning.pinned) // we failed to connect to server
 920         uri.clear();
 921     // 421: we will close due to fssError
 922     writeErrorReply(reply, 421);
 923 }
 924
 925 void
 926 Ftp::Server::handleDataReply(const HttpReply *reply, StoreIOBuffer data)
 927 {
 928     if (reply != NULL && reply->sline.status() != Http::scOkay) {
 929         writeForwardedReply(reply);
 930         if (Comm::IsConnOpen(dataConn)) {
 931             debugs(33, 3, "closing " << dataConn << " on KO reply");
 932             closeDataConnection();
 933         }
 934         return;
 935     }
 936
 937     if (!dataConn) {
 938         // We got STREAM_COMPLETE (or error) and closed the client data conn.
 939         debugs(33, 3, "ignoring FTP srv data response after clt data closure");
 940         return;
 941     }
 942
 943     if (!checkDataConnPost()) {
 944         writeCustomReply(425, "Data connection is not established.");
 945         closeDataConnection();
 946         return;
 947     }
 948
 949     debugs(33, 7, data.length);
 950
 951     if (data.length <= 0) {
 952         replyDataWritingCheckpoint(); // skip the actual write call
 953         return;
 954     }
 955
 956     MemBuf mb;
 957     mb.init(data.length + 1, data.length + 1);
 958     mb.append(data.data, data.length);
 959
 960     typedef CommCbMemFunT<Server, CommIoCbParams> Dialer;
 961     AsyncCall::Pointer call = JobCallback(33, 5, Dialer, this, Ftp::Server::wroteReplyData);
 962     Comm::Write(dataConn, &mb, call);
 963
 964     getCurrentContext()->noteSentBodyBytes(data.length);
 965 }
 966
 967 /// called when we are done writing a chunk of the response data
 968 void
 969 Ftp::Server::wroteReplyData(const CommIoCbParams &io)
 970 {
 971     if (io.flag == Comm::ERR_CLOSING)
 972         return;
 973
 974     if (io.flag != Comm::OK) {
 975         debugs(33, 3, "FTP reply data writing failed: " << xstrerr(io.xerrno));
 976         closeDataConnection();
 977         writeCustomReply(426, "Data connection error; transfer aborted");
 978         return;
 979     }
 980
 981     assert(getCurrentContext()->http);
 982     getCurrentContext()->http->out.size += io.size;
 983     replyDataWritingCheckpoint();
 984 }
 985
 986 /// ClientStream checks after (actual or skipped) reply data writing
 987 void
 988 Ftp::Server::replyDataWritingCheckpoint()
 989 {
 990     switch (getCurrentContext()->socketState()) {
 991     case STREAM_NONE:
 992         debugs(33, 3, "Keep going");
 993         getCurrentContext()->pullData();
 994         return;
 995     case STREAM_COMPLETE:
 996         debugs(33, 3, "FTP reply data transfer successfully complete");
 997         writeCustomReply(226, "Transfer complete");
 998         break;
 999     case STREAM_UNPLANNED_COMPLETE:
1000         debugs(33, 3, "FTP reply data transfer failed: STREAM_UNPLANNED_COMPLETE");
1001         writeCustomReply(451, "Server error; transfer aborted");
1002         break;
1003     case STREAM_FAILED:
1004         debugs(33, 3, "FTP reply data transfer failed: STREAM_FAILED");
1005         writeCustomReply(451, "Server error; transfer aborted");
1006         break;
1007     default:
1008         fatal("unreachable code");
1009     }
1010
1011     closeDataConnection();
1012 }
1013
1014 void
1015 Ftp::Server::handleUploadReply(const HttpReply *reply, StoreIOBuffer)
1016 {
1017     writeForwardedReply(reply);
1018     // note that the client data connection may already be closed by now
1019 }
1020
1021 void
1022 Ftp::Server::writeForwardedReply(const HttpReply *reply)
1023 {
1024     assert(reply != NULL);
1025     const HttpHeader &header = reply->header;
1026     // adaptation and forwarding errors lack HDR_FTP_STATUS
1027     if (!header.has(HDR_FTP_STATUS)) {
1028         writeForwardedForeign(reply); // will get to Ftp::Server::wroteReply
1029         return;
1030     }
1031
1032     typedef CommCbMemFunT<Server, CommIoCbParams> Dialer;
1033     AsyncCall::Pointer call = JobCallback(33, 5, Dialer, this, Ftp::Server::wroteReply);
1034     writeForwardedReplyAndCall(reply, call);
1035 }
1036
1037 void
1038 Ftp::Server::handleEprtReply(const HttpReply *reply, StoreIOBuffer)
1039 {
1040     if (getCurrentContext()->http->request->errType != ERR_NONE) {
1041         writeCustomReply(502, "Server does not support PASV (converted from EPRT)", reply);
1042         return;
1043     }
1044
1045     writeCustomReply(200, "EPRT successfully converted to PASV.");
1046
1047     // and wait for RETR
1048 }
1049
1050 void
1051 Ftp::Server::handleEpsvReply(const HttpReply *reply, StoreIOBuffer)
1052 {
1053     if (getCurrentContext()->http->request->errType != ERR_NONE) {
1054         writeCustomReply(502, "Cannot connect to server", reply);
1055         return;
1056     }
1057
1058     const unsigned short localPort = listenForDataConnection();
1059     if (!localPort)
1060         return;
1061
1062     // In interception setups, we use a local port number and hope that data
1063     // traffic will be redirected to us.
1064     MemBuf mb;
1065     mb.init();
1066     mb.Printf("229 Entering Extended Passive Mode (|||%u|)\r\n", localPort);
1067
1068     debugs(9, 3, Raw("writing", mb.buf, mb.size));
1069     writeReply(mb);
1070 }
1071
1072 /// writes FTP error response with given status and reply-derived error details
1073 void
1074 Ftp::Server::writeErrorReply(const HttpReply *reply, const int scode)
1075 {
1076     const HttpRequest *request = getCurrentContext()->http->request;
1077     assert(request);
1078
1079     MemBuf mb;
1080     mb.init();
1081
1082     if (request->errType != ERR_NONE)
1083         mb.Printf("%i-%s\r\n", scode, errorPageName(request->errType));
1084
1085     if (request->errDetail > 0) {
1086         // XXX: > 0 may not always mean that this is an errno
1087         mb.Printf("%i-Error: (%d) %s\r\n", scode,
1088                   request->errDetail,
1089                   strerror(request->errDetail));
1090     }
1091
1092 #if USE_ADAPTATION
1093     // XXX: Remove hard coded names. Use an error page template instead.
1094     const Adaptation::History::Pointer ah = request->adaptHistory();
1095     if (ah != NULL) { // XXX: add adapt::<all_h but use lastMeta here
1096         const String info = ah->allMeta.getByName("X-Response-Info");
1097         const String desc = ah->allMeta.getByName("X-Response-Desc");
1098         if (info.size())
1099             mb.Printf("%i-Information: %s\r\n", scode, info.termedBuf());
1100         if (desc.size())
1101             mb.Printf("%i-Description: %s\r\n", scode, desc.termedBuf());
1102     }
1103 #endif
1104
1105     assert(reply != NULL);
1106     const char *reason = reply->header.has(HDR_FTP_REASON) ?
1107                          reply->header.getStr(HDR_FTP_REASON):
1108                          reply->sline.reason();
1109
1110     mb.Printf("%i %s\r\n", scode, reason); // error terminating line
1111
1112     // TODO: errorpage.cc should detect FTP client and use
1113     // configurable FTP-friendly error templates which we should
1114     // write to the client "as is" instead of hiding most of the info
1115
1116     writeReply(mb);
1117 }
1118
1119 /// writes FTP response based on HTTP reply that is not an FTP-response wrapper
1120 /// for example, internally-generated Squid "errorpages" end up here (for now)
1121 void
1122 Ftp::Server::writeForwardedForeign(const HttpReply *reply)
1123 {
1124     changeState(fssConnected, "foreign reply");
1125     closeDataConnection();
1126     // 451: We intend to keep the control connection open.
1127     writeErrorReply(reply, 451);
1128 }
1129
1130 void
1131 Ftp::Server::writeControlMsgAndCall(ClientSocketContext *context, HttpReply *reply, AsyncCall::Pointer &call)
1132 {
1133     // the caller guarantees that we are dealing with the current context only
1134     // the caller should also make sure reply->header.has(HDR_FTP_STATUS)
1135     writeForwardedReplyAndCall(reply, call);
1136 }
1137
1138 void
1139 Ftp::Server::writeForwardedReplyAndCall(const HttpReply *reply, AsyncCall::Pointer &call)
1140 {
1141     assert(reply != NULL);
1142     const HttpHeader &header = reply->header;
1143
1144     // without status, the caller must use the writeForwardedForeign() path
1145     Must(header.has(HDR_FTP_STATUS));
1146     Must(header.has(HDR_FTP_REASON));
1147     const int scode = header.getInt(HDR_FTP_STATUS);
1148     debugs(33, 7, "scode: " << scode);
1149
1150     // Status 125 or 150 implies upload or data request, but we still check
1151     // the state in case the server is buggy.
1152     if ((scode == 125 || scode == 150) &&
1153             (master->serverState == fssHandleUploadRequest ||
1154              master->serverState == fssHandleDataRequest)) {
1155         if (checkDataConnPost()) {
1156             // If the data connection is ready, start reading data (here)
1157             // and forward the response to client (further below).
1158             debugs(33, 7, "data connection established, start data transfer");
1159             if (master->serverState == fssHandleUploadRequest)
1160                 maybeReadUploadData();
1161         } else {
1162             // If we are waiting to accept the data connection, keep waiting.
1163             if (Comm::IsConnOpen(dataListenConn)) {
1164                 debugs(33, 7, "wait for the client to establish a data connection");
1165                 onDataAcceptCall = call;
1166                 // TODO: Add connect timeout for passive connections listener?
1167                 // TODO: Remember server response so that we can forward it?
1168             } else {
1169                 // Either the connection was establised and closed after the
1170                 // data was transferred OR we failed to establish an active
1171                 // data connection and already sent the error to the client.
1172                 // In either case, there is nothing more to do.
1173                 debugs(33, 7, "done with data OR active connection failed");
1174             }
1175             return;
1176         }
1177     }
1178
1179     MemBuf mb;
1180     mb.init();
1181     Ftp::PrintReply(mb, reply);
1182
1183     debugs(9, 2, "FTP Client " << clientConnection);
1184     debugs(9, 2, "FTP Client REPLY:\n---------\n" << mb.buf <<
1185            "\n----------");
1186
1187     Comm::Write(clientConnection, &mb, call);
1188 }
1189
1190 static void
1191 Ftp::PrintReply(MemBuf &mb, const HttpReply *reply, const char *const prefix)
1192 {
1193     const HttpHeader &header = reply->header;
1194
1195     HttpHeaderPos pos = HttpHeaderInitPos;
1196     while (const HttpHeaderEntry *e = header.getEntry(&pos)) {
1197         if (e->id == HDR_FTP_PRE) {
1198             String raw;
1199             if (httpHeaderParseQuotedString(e->value.rawBuf(), e->value.size(), &raw))
1200                 mb.Printf("%s\r\n", raw.termedBuf());
1201         }
1202     }
1203
1204     if (header.has(HDR_FTP_STATUS)) {
1205         const char *reason = header.getStr(HDR_FTP_REASON);
1206         mb.Printf("%i %s\r\n", header.getInt(HDR_FTP_STATUS),
1207                   (reason ? reason : 0));
1208     }
1209 }
1210
1211 void
1212 Ftp::Server::wroteEarlyReply(const CommIoCbParams &io)
1213 {
1214     if (io.flag == Comm::ERR_CLOSING)
1215         return;
1216
1217     if (io.flag != Comm::OK) {
1218         debugs(33, 3, "FTP reply writing failed: " << xstrerr(io.xerrno));
1219         io.conn->close();
1220         return;
1221     }
1222
1223     ClientSocketContext::Pointer context = getCurrentContext();
1224     if (context != NULL && context->http) {
1225         context->http->out.size += io.size;
1226         context->http->out.headers_sz += io.size;
1227     }
1228
1229     flags.readMore = true;
1230     readSomeData();
1231 }
1232
1233 void
1234 Ftp::Server::wroteReply(const CommIoCbParams &io)
1235 {
1236     if (io.flag == Comm::ERR_CLOSING)
1237         return;
1238
1239     if (io.flag != Comm::OK) {
1240         debugs(33, 3, "FTP reply writing failed: " << xstrerr(io.xerrno));
1241         io.conn->close();
1242         return;
1243     }
1244
1245     ClientSocketContext::Pointer context = getCurrentContext();
1246     assert(context->http);
1247     context->http->out.size += io.size;
1248     context->http->out.headers_sz += io.size;
1249
1250     if (master->serverState == fssError) {
1251         debugs(33, 5, "closing on FTP server error");
1252         io.conn->close();
1253         return;
1254     }
1255
1256     const clientStream_status_t socketState = context->socketState();
1257     debugs(33, 5, "FTP client stream state " << socketState);
1258     switch (socketState) {
1259     case STREAM_UNPLANNED_COMPLETE:
1260     case STREAM_FAILED:
1261         io.conn->close();
1262         return;
1263
1264     case STREAM_NONE:
1265     case STREAM_COMPLETE:
1266         flags.readMore = true;
1267         changeState(fssConnected, "Ftp::Server::wroteReply");
1268         if (in.bodyParser)
1269             finishDechunkingRequest(false);
1270         context->keepaliveNextRequest();
1271         return;
1272     }
1273 }
1274
1275 bool
1276 Ftp::Server::handleRequest(HttpRequest *request)
1277 {
1278     debugs(33, 9, request);
1279     Must(request);
1280
1281     HttpHeader &header = request->header;
1282     Must(header.has(HDR_FTP_COMMAND));
1283     String &cmd = header.findEntry(HDR_FTP_COMMAND)->value;
1284     Must(header.has(HDR_FTP_ARGUMENTS));
1285     String &params = header.findEntry(HDR_FTP_ARGUMENTS)->value;
1286
1287     if (do_debug(9, 2)) {
1288         MemBuf mb;
1289         Packer p;
1290         mb.init();
1291         packerToMemInit(&p, &mb);
1292         request->pack(&p);
1293         packerClean(&p);
1294
1295         debugs(9, 2, "FTP Client " << clientConnection);
1296         debugs(9, 2, "FTP Client REQUEST:\n---------\n" << mb.buf <<
1297                "\n----------");
1298     }
1299
1300     // TODO: When HttpHeader uses SBuf, change keys to SBuf
1301     typedef std::map<const std::string, RequestHandler> RequestHandlers;
1302     static RequestHandlers handlers;
1303     if (!handlers.size()) {
1304         handlers["LIST"] = &Ftp::Server::handleDataRequest;
1305         handlers["NLST"] = &Ftp::Server::handleDataRequest;
1306         handlers["MLSD"] = &Ftp::Server::handleDataRequest;
1307         handlers["FEAT"] = &Ftp::Server::handleFeatRequest;
1308         handlers["PASV"] = &Ftp::Server::handlePasvRequest;
1309         handlers["PORT"] = &Ftp::Server::handlePortRequest;
1310         handlers["RETR"] = &Ftp::Server::handleDataRequest;
1311         handlers["EPRT"] = &Ftp::Server::handleEprtRequest;
1312         handlers["EPSV"] = &Ftp::Server::handleEpsvRequest;
1313         handlers["CWD"] = &Ftp::Server::handleCwdRequest;
1314         handlers["PASS"] = &Ftp::Server::handlePassRequest;
1315         handlers["CDUP"] = &Ftp::Server::handleCdupRequest;
1316     }
1317
1318     RequestHandler handler = NULL;
1319     if (request->method == Http::METHOD_PUT)
1320         handler = &Ftp::Server::handleUploadRequest;
1321     else {
1322         const RequestHandlers::const_iterator hi = handlers.find(cmd.termedBuf());
1323         if (hi != handlers.end())
1324             handler = hi->second;
1325     }
1326
1327     if (!handler) {
1328         debugs(9, 7, "forwarding " << cmd << " as is, no post-processing");
1329         return true;
1330     }
1331
1332     return (this->*handler)(cmd, params);
1333 }
1334
1335 /// Called to parse USER command, which is required to create an HTTP request
1336 /// wrapper. W/o request, the errors are handled by returning earlyError().
1337 ClientSocketContext *
1338 Ftp::Server::handleUserRequest(const SBuf &cmd, SBuf &params)
1339 {
1340     if (params.isEmpty())
1341         return earlyError(eekMissingUsername);
1342
1343     // find the [end of] user name
1344     const SBuf::size_type eou = params.rfind('@');
1345     if (eou == SBuf::npos || eou + 1 >= params.length())
1346         return earlyError(eekMissingHost);
1347
1348     // Determine the intended destination.
1349     host = params.substr(eou + 1, params.length());
1350     // If we can parse it as raw IPv6 address, then surround with "[]".
1351     // Otherwise (domain, IPv4, [bracketed] IPv6, garbage, etc), use as is.
1352     if (host.find(':') != SBuf::npos) {
1353         const Ip::Address ipa(host.c_str());
1354         if (!ipa.isAnyAddr()) {
1355             char ipBuf[MAX_IPSTRLEN];
1356             ipa.toHostStr(ipBuf, MAX_IPSTRLEN);
1357             host = ipBuf;
1358         }
1359     }
1360
1361     // const SBuf login = params.substr(0, eou);
1362     params.chop(0, eou); // leave just the login part for the peer
1363
1364     SBuf oldUri;
1365     if (master->clientReadGreeting)
1366         oldUri = uri;
1367
1368     master->workingDir.clear();
1369     calcUri(NULL);
1370
1371     if (!master->clientReadGreeting) {
1372         debugs(9, 3, "set URI to " << uri);
1373     } else if (oldUri.caseCmp(uri) == 0) {
1374         debugs(9, 5, "kept URI as " << oldUri);
1375     } else {
1376         debugs(9, 3, "reset URI from " << oldUri << " to " << uri);
1377         closeDataConnection();
1378         unpinConnection(true); // close control connection to peer
1379         resetLogin("URI reset");
1380     }
1381
1382     return NULL; // no early errors
1383 }
1384
1385 bool
1386 Ftp::Server::handleFeatRequest(String &cmd, String &params)
1387 {
1388     changeState(fssHandleFeat, "handleFeatRequest");
1389     return true;
1390 }
1391
1392 bool
1393 Ftp::Server::handlePasvRequest(String &cmd, String &params)
1394 {
1395     if (gotEpsvAll) {
1396         setReply(500, "Bad PASV command");
1397         return false;
1398     }
1399
1400     if (params.size() > 0) {
1401         setReply(501, "Unexpected parameter");
1402         return false;
1403     }
1404
1405     changeState(fssHandlePasv, "handlePasvRequest");
1406     // no need to fake PASV request via setDataCommand() in true PASV case
1407     return true;
1408 }
1409
1410 /// [Re]initializes dataConn for active data transfers. Does not connect.
1411 bool
1412 Ftp::Server::createDataConnection(Ip::Address cltAddr)
1413 {
1414     assert(clientConnection != NULL);
1415     assert(!clientConnection->remote.isAnyAddr());
1416
1417     if (cltAddr != clientConnection->remote) {
1418         debugs(33, 2, "rogue PORT " << cltAddr << " request? ctrl: " << clientConnection->remote);
1419         // Closing the control connection would not help with attacks because
1420         // the client is evidently able to connect to us. Besides, closing
1421         // makes retrials easier for the client and more damaging to us.
1422         setReply(501, "Prohibited parameter value");
1423         return false;
1424     }
1425
1426     closeDataConnection();
1427
1428     Comm::ConnectionPointer conn = new Comm::Connection();
1429     conn->flags |= COMM_DOBIND;
1430
1431     // Use local IP address of the control connection as the source address
1432     // of the active data connection, or some clients will refuse to accept.
1433     conn->setAddrs(clientConnection->local, cltAddr);
1434     // RFC 959 requires active FTP connections to originate from port 20
1435     // but that would preclude us from supporting concurrent transfers! (XXX?)
1436     conn->local.port(0);
1437
1438     debugs(9, 3, "will actively connect from " << conn->local << " to " <<
1439            conn->remote);
1440
1441     dataConn = conn;
1442     uploadAvailSize = 0;
1443     return true;
1444 }
1445
1446 bool
1447 Ftp::Server::handlePortRequest(String &cmd, String &params)
1448 {
1449     // TODO: Should PORT errors trigger closeDataConnection() cleanup?
1450
1451     if (gotEpsvAll) {
1452         setReply(500, "Rejecting PORT after EPSV ALL");
1453         return false;
1454     }
1455
1456     if (!params.size()) {
1457         setReply(501, "Missing parameter");
1458         return false;
1459     }
1460
1461     Ip::Address cltAddr;
1462     if (!Ftp::ParseIpPort(params.termedBuf(), NULL, cltAddr)) {
1463         setReply(501, "Invalid parameter");
1464         return false;
1465     }
1466
1467     if (!createDataConnection(cltAddr))
1468         return false;
1469
1470     changeState(fssHandlePort, "handlePortRequest");
1471     setDataCommand();
1472     return true; // forward our fake PASV request
1473 }
1474
1475 bool
1476 Ftp::Server::handleDataRequest(String &cmd, String &params)
1477 {
1478     if (!checkDataConnPre())
1479         return false;
1480
1481     changeState(fssHandleDataRequest, "handleDataRequest");
1482
1483     return true;
1484 }
1485
1486 bool
1487 Ftp::Server::handleUploadRequest(String &cmd, String &params)
1488 {
1489     if (!checkDataConnPre())
1490         return false;
1491
1492     if (Config.accessList.forceRequestBodyContinuation) {
1493         ClientHttpRequest *http = getCurrentContext()->http;
1494         HttpRequest *request = http->request;
1495         ACLFilledChecklist bodyContinuationCheck(Config.accessList.forceRequestBodyContinuation, request, NULL);
1496         if (bodyContinuationCheck.fastCheck() == ACCESS_ALLOWED) {
1497             request->forcedBodyContinuation = true;
1498             if (checkDataConnPost()) {
1499                 // Write control Msg
1500                 writeEarlyReply(150, "Data connection opened");
1501                 maybeReadUploadData();
1502             } else {
1503                 // wait for acceptDataConnection but tell it to call wroteEarlyReply
1504                 // after writing "150 Data connection opened"
1505                 typedef CommCbMemFunT<Server, CommIoCbParams> Dialer;
1506                 AsyncCall::Pointer call = JobCallback(33, 5, Dialer, this, Ftp::Server::wroteEarlyReply);
1507                 onDataAcceptCall = call;
1508             }
1509         }
1510     }
1511
1512     changeState(fssHandleUploadRequest, "handleDataRequest");
1513
1514     return true;
1515 }
1516
1517 bool
1518 Ftp::Server::handleEprtRequest(String &cmd, String &params)
1519 {
1520     debugs(9, 3, "Process an EPRT " << params);
1521
1522     if (gotEpsvAll) {
1523         setReply(500, "Rejecting EPRT after EPSV ALL");
1524         return false;
1525     }
1526
1527     if (!params.size()) {
1528         setReply(501, "Missing parameter");
1529         return false;
1530     }
1531
1532     Ip::Address cltAddr;
1533     if (!Ftp::ParseProtoIpPort(params.termedBuf(), cltAddr)) {
1534         setReply(501, "Invalid parameter");
1535         return false;
1536     }
1537
1538     if (!createDataConnection(cltAddr))
1539         return false;
1540
1541     changeState(fssHandleEprt, "handleEprtRequest");
1542     setDataCommand();
1543     return true; // forward our fake PASV request
1544 }
1545
1546 bool
1547 Ftp::Server::handleEpsvRequest(String &cmd, String &params)
1548 {
1549     debugs(9, 3, "Process an EPSV command with params: " << params);
1550     if (params.size() <= 0) {
1551         // treat parameterless EPSV as "use the protocol of the ctrl conn"
1552     } else if (params.caseCmp("ALL") == 0) {
1553         setReply(200, "EPSV ALL ok");
1554         gotEpsvAll = true;
1555         return false;
1556     } else if (params.cmp("2") == 0) {
1557         if (!Ip::EnableIpv6) {
1558             setReply(522, "Network protocol not supported, use (1)");
1559             return false;
1560         }
1561     } else if (params.cmp("1") != 0) {
1562         setReply(501, "Unsupported EPSV parameter");
1563         return false;
1564     }
1565
1566     changeState(fssHandleEpsv, "handleEpsvRequest");
1567     setDataCommand();
1568     return true; // forward our fake PASV request
1569 }
1570
1571 bool
1572 Ftp::Server::handleCwdRequest(String &cmd, String &params)
1573 {
1574     changeState(fssHandleCwd, "handleCwdRequest");
1575     return true;
1576 }
1577
1578 bool
1579 Ftp::Server::handlePassRequest(String &cmd, String &params)
1580 {
1581     changeState(fssHandlePass, "handlePassRequest");
1582     return true;
1583 }
1584
1585 bool
1586 Ftp::Server::handleCdupRequest(String &cmd, String &params)
1587 {
1588     changeState(fssHandleCdup, "handleCdupRequest");
1589     return true;
1590 }
1591
1592 // Convert user PORT, EPRT, PASV, or EPSV data command to Squid PASV command.
1593 // Squid FTP client decides what data command to use with peers.
1594 void
1595 Ftp::Server::setDataCommand()
1596 {
1597     ClientHttpRequest *const http = getCurrentContext()->http;
1598     assert(http != NULL);
1599     HttpRequest *const request = http->request;
1600     assert(request != NULL);
1601     HttpHeader &header = request->header;
1602     header.delById(HDR_FTP_COMMAND);
1603     header.putStr(HDR_FTP_COMMAND, "PASV");
1604     header.delById(HDR_FTP_ARGUMENTS);
1605     header.putStr(HDR_FTP_ARGUMENTS, "");
1606     debugs(9, 5, "client data command converted to fake PASV");
1607 }
1608
1609 /// check that client data connection is ready for future I/O or at least
1610 /// has a chance of becoming ready soon.
1611 bool
1612 Ftp::Server::checkDataConnPre()
1613 {
1614     if (Comm::IsConnOpen(dataConn))
1615         return true;
1616
1617     if (Comm::IsConnOpen(dataListenConn)) {
1618         // We are still waiting for a client to connect to us after PASV.
1619         // Perhaps client's data conn handshake has not reached us yet.
1620         // After we talk to the server, checkDataConnPost() will recheck.
1621         debugs(33, 3, "expecting clt data conn " << dataListenConn);
1622         return true;
1623     }
1624
1625     if (!dataConn || dataConn->remote.isAnyAddr()) {
1626         debugs(33, 5, "missing " << dataConn);
1627         // TODO: use client address and default port instead.
1628         setReply(425, "Use PORT or PASV first");
1629         return false;
1630     }
1631
1632     // active transfer: open a data connection from Squid to client
1633     typedef CommCbMemFunT<Server, CommConnectCbParams> Dialer;
1634     connector = JobCallback(17, 3, Dialer, this, Ftp::Server::connectedForData);
1635     Comm::ConnOpener *cs = new Comm::ConnOpener(dataConn, connector,
1636             Config.Timeout.connect);
1637     AsyncJob::Start(cs);
1638     return false; // ConnStateData::processFtpRequest waits handleConnectDone
1639 }
1640
1641 /// Check that client data connection is ready for immediate I/O.
1642 bool
1643 Ftp::Server::checkDataConnPost() const
1644 {
1645     if (!Comm::IsConnOpen(dataConn)) {
1646         debugs(33, 3, "missing client data conn: " << dataConn);
1647         return false;
1648     }
1649     return true;
1650 }
1651
1652 /// Done establishing a data connection to the user.
1653 void
1654 Ftp::Server::connectedForData(const CommConnectCbParams &params)
1655 {
1656     connector = NULL;
1657
1658     if (params.flag != Comm::OK) {
1659         /* it might have been a timeout with a partially open link */
1660         if (params.conn != NULL)
1661             params.conn->close();
1662         setReply(425, "Cannot open data connection.");
1663         ClientSocketContext::Pointer context = getCurrentContext();
1664         Must(context->http);
1665         Must(context->http->storeEntry() != NULL);
1666     } else {
1667         Must(dataConn == params.conn);
1668         Must(Comm::IsConnOpen(params.conn));
1669         fd_note(params.conn->fd, "active client ftp data");
1670     }
1671
1672     doProcessRequest();
1673 }
1674
1675 void
1676 Ftp::Server::setReply(const int code, const char *msg)
1677 {
1678     ClientSocketContext::Pointer context = getCurrentContext();
1679     ClientHttpRequest *const http = context->http;
1680     assert(http != NULL);
1681     assert(http->storeEntry() == NULL);
1682
1683     HttpReply *const reply = Ftp::HttpReplyWrapper(code, msg, Http::scNoContent, 0);
1684
1685     setLogUri(http, urlCanonicalClean(http->request));
1686
1687     clientStreamNode *const node = context->getClientReplyContext();
1688     clientReplyContext *const repContext =
1689         dynamic_cast<clientReplyContext *>(node->data.getRaw());
1690     assert(repContext != NULL);
1691
1692     RequestFlags reqFlags;
1693     reqFlags.cachable = false; // force releaseRequest() in storeCreateEntry()
1694     reqFlags.noCache = true;
1695     repContext->createStoreEntry(http->request->method, reqFlags);
1696     http->storeEntry()->replaceHttpReply(reply);
1697 }
1698
1699 /// Whether Squid FTP Relay supports a named feature (e.g., a command).
1700 static bool
1701 Ftp::SupportedCommand(const SBuf &name)
1702 {
1703     static std::set<SBuf> BlackList;
1704     if (BlackList.empty()) {
1705         /* Add FTP commands that Squid cannot relay correctly. */
1706
1707         // We probably do not support AUTH TLS.* and AUTH SSL,
1708         // but let's disclaim all AUTH support to KISS, for now.
1709         BlackList.insert(cmdAuth());
1710     }
1711
1712     // we claim support for all commands that we do not know about
1713     return BlackList.find(name) == BlackList.end();
1714 }
1715