methods/http.cc

   1 // -*- mode: cpp; mode: fold -*-
   2 // Description                                                          /*{{{*/
   3 // $Id: http.cc,v 1.59 2004/05/08 19:42:35 mdz Exp $
   4 /* ######################################################################
   5
   6    HTTP Acquire Method - This is the HTTP aquire method for APT.
   7
   8    It uses HTTP/1.1 and many of the fancy options there-in, such as
   9    pipelining, range, if-range and so on.
  10
  11    It is based on a doubly buffered select loop. A groupe of requests are
  12    fed into a single output buffer that is constantly fed out the
  13    socket. This provides ideal pipelining as in many cases all of the
  14    requests will fit into a single packet. The input socket is buffered
  15    the same way and fed into the fd for the file (may be a pipe in future).
  16
  17    This double buffering provides fairly substantial transfer rates,
  18    compared to wget the http method is about 4% faster. Most importantly,
  19    when HTTP is compared with FTP as a protocol the speed difference is
  20    huge. In tests over the internet from two sites to llug (via ATM) this
  21    program got 230k/s sustained http transfer rates. FTP on the other
  22    hand topped out at 170k/s. That combined with the time to setup the
  23    FTP connection makes HTTP a vastly superior protocol.
  24
  25    ##################################################################### */
  26                                                                         /*}}}*/
  27 // Include Files                                                        /*{{{*/
  28 #include <apt-pkg/fileutl.h>
  29 #include <apt-pkg/acquire-method.h>
  30 #include <apt-pkg/error.h>
  31 #include <apt-pkg/hashes.h>
  32 #include <apt-pkg/netrc.h>
  33
  34 #include <sys/stat.h>
  35 #include <sys/time.h>
  36 #include <utime.h>
  37 #include <unistd.h>
  38 #include <signal.h>
  39 #include <stdio.h>
  40 #include <errno.h>
  41 #include <string.h>
  42 #include <iostream>
  43 #include <map>
  44 #include <apti18n.h>
  45
  46
  47 // Internet stuff
  48 #include <netdb.h>
  49
  50 #include "config.h"
  51 #include "connect.h"
  52 #include "rfc2553emu.h"
  53 #include "http.h"
  54                                                                         /*}}}*/
  55 using namespace std;
  56
  57 string HttpMethod::FailFile;
  58 int HttpMethod::FailFd = -1;
  59 time_t HttpMethod::FailTime = 0;
  60 unsigned long PipelineDepth = 10;
  61 unsigned long TimeOut = 120;
  62 bool AllowRedirect = false;
  63 bool Debug = false;
  64 URI Proxy;
  65
  66 unsigned long CircleBuf::BwReadLimit=0;
  67 unsigned long CircleBuf::BwTickReadData=0;
  68 struct timeval CircleBuf::BwReadTick={0,0};
  69 const unsigned int CircleBuf::BW_HZ=10;
  70
  71 // CircleBuf::CircleBuf - Circular input buffer                         /*{{{*/
  72 // ---------------------------------------------------------------------
  73 /* */
  74 CircleBuf::CircleBuf(unsigned long Size) : Size(Size), Hash(0)
  75 {
  76    Buf = new unsigned char[Size];
  77    Reset();
  78
  79    CircleBuf::BwReadLimit = _config->FindI("Acquire::http::Dl-Limit",0)*1024;
  80 }
  81                                                                         /*}}}*/
  82 // CircleBuf::Reset - Reset to the default state                        /*{{{*/
  83 // ---------------------------------------------------------------------
  84 /* */
  85 void CircleBuf::Reset()
  86 {
  87    InP = 0;
  88    OutP = 0;
  89    StrPos = 0;
  90    MaxGet = (unsigned int)-1;
  91    OutQueue = string();
  92    if (Hash != 0)
  93    {
  94       delete Hash;
  95       Hash = new Hashes;
  96    }
  97 };
  98                                                                         /*}}}*/
  99 // CircleBuf::Read - Read from a FD into the circular buffer            /*{{{*/
 100 // ---------------------------------------------------------------------
 101 /* This fills up the buffer with as much data as is in the FD, assuming it
 102    is non-blocking.. */
 103 bool CircleBuf::Read(int Fd)
 104 {
 105    unsigned long BwReadMax;
 106
 107    while (1)
 108    {
 109       // Woops, buffer is full
 110       if (InP - OutP == Size)
 111          return true;
 112
 113       // what's left to read in this tick
 114       BwReadMax = CircleBuf::BwReadLimit/BW_HZ;
 115
 116       if(CircleBuf::BwReadLimit) {
 117          struct timeval now;
 118          gettimeofday(&now,0);
 119
 120          unsigned long d = (now.tv_sec-CircleBuf::BwReadTick.tv_sec)*1000000 +
 121             now.tv_usec-CircleBuf::BwReadTick.tv_usec;
 122          if(d > 1000000/BW_HZ) {
 123             CircleBuf::BwReadTick = now;
 124             CircleBuf::BwTickReadData = 0;
 125          }
 126
 127          if(CircleBuf::BwTickReadData >= BwReadMax) {
 128             usleep(1000000/BW_HZ);
 129             return true;
 130          }
 131       }
 132
 133       // Write the buffer segment
 134       int Res;
 135       if(CircleBuf::BwReadLimit) {
 136          Res = read(Fd,Buf + (InP%Size),
 137                     BwReadMax > LeftRead() ? LeftRead() : BwReadMax);
 138       } else
 139          Res = read(Fd,Buf + (InP%Size),LeftRead());
 140
 141       if(Res > 0 && BwReadLimit > 0)
 142          CircleBuf::BwTickReadData += Res;
 143
 144       if (Res == 0)
 145          return false;
 146       if (Res < 0)
 147       {
 148          if (errno == EAGAIN)
 149             return true;
 150          return false;
 151       }
 152
 153       if (InP == 0)
 154          gettimeofday(&Start,0);
 155       InP += Res;
 156    }
 157 }
 158                                                                         /*}}}*/
 159 // CircleBuf::Read - Put the string into the buffer                     /*{{{*/
 160 // ---------------------------------------------------------------------
 161 /* This will hold the string in and fill the buffer with it as it empties */
 162 bool CircleBuf::Read(string Data)
 163 {
 164    OutQueue += Data;
 165    FillOut();
 166    return true;
 167 }
 168                                                                         /*}}}*/
 169 // CircleBuf::FillOut - Fill the buffer from the output queue           /*{{{*/
 170 // ---------------------------------------------------------------------
 171 /* */
 172 void CircleBuf::FillOut()
 173 {
 174    if (OutQueue.empty() == true)
 175       return;
 176    while (1)
 177    {
 178       // Woops, buffer is full
 179       if (InP - OutP == Size)
 180          return;
 181
 182       // Write the buffer segment
 183       unsigned long Sz = LeftRead();
 184       if (OutQueue.length() - StrPos < Sz)
 185          Sz = OutQueue.length() - StrPos;
 186       memcpy(Buf + (InP%Size),OutQueue.c_str() + StrPos,Sz);
 187
 188       // Advance
 189       StrPos += Sz;
 190       InP += Sz;
 191       if (OutQueue.length() == StrPos)
 192       {
 193          StrPos = 0;
 194          OutQueue = "";
 195          return;
 196       }
 197    }
 198 }
 199                                                                         /*}}}*/
 200 // CircleBuf::Write - Write from the buffer into a FD                   /*{{{*/
 201 // ---------------------------------------------------------------------
 202 /* This empties the buffer into the FD. */
 203 bool CircleBuf::Write(int Fd)
 204 {
 205    while (1)
 206    {
 207       FillOut();
 208
 209       // Woops, buffer is empty
 210       if (OutP == InP)
 211          return true;
 212
 213       if (OutP == MaxGet)
 214          return true;
 215
 216       // Write the buffer segment
 217       int Res;
 218       Res = write(Fd,Buf + (OutP%Size),LeftWrite());
 219
 220       if (Res == 0)
 221          return false;
 222       if (Res < 0)
 223       {
 224          if (errno == EAGAIN)
 225             return true;
 226
 227          return false;
 228       }
 229
 230       if (Hash != 0)
 231          Hash->Add(Buf + (OutP%Size),Res);
 232
 233       OutP += Res;
 234    }
 235 }
 236                                                                         /*}}}*/
 237 // CircleBuf::WriteTillEl - Write from the buffer to a string           /*{{{*/
 238 // ---------------------------------------------------------------------
 239 /* This copies till the first empty line */
 240 bool CircleBuf::WriteTillEl(string &Data,bool Single)
 241 {
 242    // We cheat and assume it is unneeded to have more than one buffer load
 243    for (unsigned long I = OutP; I < InP; I++)
 244    {
 245       if (Buf[I%Size] != '\n')
 246          continue;
 247       ++I;
 248
 249       if (Single == false)
 250       {
 251          if (I < InP  && Buf[I%Size] == '\r')
 252             ++I;
 253          if (I >= InP || Buf[I%Size] != '\n')
 254             continue;
 255          ++I;
 256       }
 257
 258       Data = "";
 259       while (OutP < I)
 260       {
 261          unsigned long Sz = LeftWrite();
 262          if (Sz == 0)
 263             return false;
 264          if (I - OutP < Sz)
 265             Sz = I - OutP;
 266          Data += string((char *)(Buf + (OutP%Size)),Sz);
 267          OutP += Sz;
 268       }
 269       return true;
 270    }
 271    return false;
 272 }
 273                                                                         /*}}}*/
 274 // CircleBuf::Stats - Print out stats information                       /*{{{*/
 275 // ---------------------------------------------------------------------
 276 /* */
 277 void CircleBuf::Stats()
 278 {
 279    if (InP == 0)
 280       return;
 281
 282    struct timeval Stop;
 283    gettimeofday(&Stop,0);
 284 /*   float Diff = Stop.tv_sec - Start.tv_sec +
 285              (float)(Stop.tv_usec - Start.tv_usec)/1000000;
 286    clog << "Got " << InP << " in " << Diff << " at " << InP/Diff << endl;*/
 287 }
 288                                                                         /*}}}*/
 289
 290 // ServerState::ServerState - Constructor                               /*{{{*/
 291 // ---------------------------------------------------------------------
 292 /* */
 293 ServerState::ServerState(URI Srv,HttpMethod *Owner) : Owner(Owner),
 294                         In(64*1024), Out(4*1024),
 295                         ServerName(Srv)
 296 {
 297    Reset();
 298 }
 299                                                                         /*}}}*/
 300 // ServerState::Open - Open a connection to the server                  /*{{{*/
 301 // ---------------------------------------------------------------------
 302 /* This opens a connection to the server. */
 303 bool ServerState::Open()
 304 {
 305    // Use the already open connection if possible.
 306    if (ServerFd != -1)
 307       return true;
 308
 309    Close();
 310    In.Reset();
 311    Out.Reset();
 312    Persistent = true;
 313
 314    // Determine the proxy setting
 315    string SpecificProxy = _config->Find("Acquire::http::Proxy::" + ServerName.Host);
 316    if (!SpecificProxy.empty())
 317    {
 318            if (SpecificProxy == "DIRECT")
 319                    Proxy = "";
 320            else
 321                    Proxy = SpecificProxy;
 322    }
 323    else
 324    {
 325            string DefProxy = _config->Find("Acquire::http::Proxy");
 326            if (!DefProxy.empty())
 327            {
 328                    Proxy = DefProxy;
 329            }
 330            else
 331            {
 332                    char* result = getenv("http_proxy");
 333                    Proxy = result ? result : "";
 334            }
 335    }
 336
 337    // Parse no_proxy, a , separated list of domains
 338    if (getenv("no_proxy") != 0)
 339    {
 340       if (CheckDomainList(ServerName.Host,getenv("no_proxy")) == true)
 341          Proxy = "";
 342    }
 343
 344    // Determine what host and port to use based on the proxy settings
 345    int Port = 0;
 346    string Host;
 347    if (Proxy.empty() == true || Proxy.Host.empty() == true)
 348    {
 349       if (ServerName.Port != 0)
 350          Port = ServerName.Port;
 351       Host = ServerName.Host;
 352    }
 353    else
 354    {
 355       if (Proxy.Port != 0)
 356          Port = Proxy.Port;
 357       Host = Proxy.Host;
 358    }
 359
 360    // Connect to the remote server
 361    if (Connect(Host,Port,"http",80,ServerFd,TimeOut,Owner) == false)
 362       return false;
 363
 364    return true;
 365 }
 366                                                                         /*}}}*/
 367 // ServerState::Close - Close a connection to the server                /*{{{*/
 368 // ---------------------------------------------------------------------
 369 /* */
 370 bool ServerState::Close()
 371 {
 372    close(ServerFd);
 373    ServerFd = -1;
 374    return true;
 375 }
 376                                                                         /*}}}*/
 377 // ServerState::RunHeaders - Get the headers before the data            /*{{{*/
 378 // ---------------------------------------------------------------------
 379 /* Returns 0 if things are OK, 1 if an IO error occurred and 2 if a header
 380    parse error occurred */
 381 int ServerState::RunHeaders()
 382 {
 383    State = Header;
 384
 385    Owner->Status(_("Waiting for headers"));
 386
 387    Major = 0;
 388    Minor = 0;
 389    Result = 0;
 390    Size = 0;
 391    StartPos = 0;
 392    Encoding = Closes;
 393    HaveContent = false;
 394    time(&Date);
 395
 396    do
 397    {
 398       string Data;
 399       if (In.WriteTillEl(Data) == false)
 400          continue;
 401
 402       if (Debug == true)
 403          clog << Data;
 404
 405       for (string::const_iterator I = Data.begin(); I < Data.end(); I++)
 406       {
 407          string::const_iterator J = I;
 408          for (; J != Data.end() && *J != '\n' && *J != '\r';J++);
 409          if (HeaderLine(string(I,J)) == false)
 410             return 2;
 411          I = J;
 412       }
 413
 414       // 100 Continue is a Nop...
 415       if (Result == 100)
 416          continue;
 417
 418       // Tidy up the connection persistance state.
 419       if (Encoding == Closes && HaveContent == true)
 420          Persistent = false;
 421
 422       return 0;
 423    }
 424    while (Owner->Go(false,this) == true);
 425
 426    return 1;
 427 }
 428                                                                         /*}}}*/
 429 // ServerState::RunData - Transfer the data from the socket             /*{{{*/
 430 // ---------------------------------------------------------------------
 431 /* */
 432 bool ServerState::RunData()
 433 {
 434    State = Data;
 435
 436    // Chunked transfer encoding is fun..
 437    if (Encoding == Chunked)
 438    {
 439       while (1)
 440       {
 441          // Grab the block size
 442          bool Last = true;
 443          string Data;
 444          In.Limit(-1);
 445          do
 446          {
 447             if (In.WriteTillEl(Data,true) == true)
 448                break;
 449          }
 450          while ((Last = Owner->Go(false,this)) == true);
 451
 452          if (Last == false)
 453             return false;
 454
 455          // See if we are done
 456          unsigned long Len = strtol(Data.c_str(),0,16);
 457          if (Len == 0)
 458          {
 459             In.Limit(-1);
 460
 461             // We have to remove the entity trailer
 462             Last = true;
 463             do
 464             {
 465                if (In.WriteTillEl(Data,true) == true && Data.length() <= 2)
 466                   break;
 467             }
 468             while ((Last = Owner->Go(false,this)) == true);
 469             if (Last == false)
 470                return false;
 471             return !_error->PendingError();
 472          }
 473
 474          // Transfer the block
 475          In.Limit(Len);
 476          while (Owner->Go(true,this) == true)
 477             if (In.IsLimit() == true)
 478                break;
 479
 480          // Error
 481          if (In.IsLimit() == false)
 482             return false;
 483
 484          // The server sends an extra new line before the next block specifier..
 485          In.Limit(-1);
 486          Last = true;
 487          do
 488          {
 489             if (In.WriteTillEl(Data,true) == true)
 490                break;
 491          }
 492          while ((Last = Owner->Go(false,this)) == true);
 493          if (Last == false)
 494             return false;
 495       }
 496    }
 497    else
 498    {
 499       /* Closes encoding is used when the server did not specify a size, the
 500          loss of the connection means we are done */
 501       if (Encoding == Closes)
 502          In.Limit(-1);
 503       else
 504          In.Limit(Size - StartPos);
 505
 506       // Just transfer the whole block.
 507       do
 508       {
 509          if (In.IsLimit() == false)
 510             continue;
 511
 512          In.Limit(-1);
 513          return !_error->PendingError();
 514       }
 515       while (Owner->Go(true,this) == true);
 516    }
 517
 518    return Owner->Flush(this) && !_error->PendingError();
 519 }
 520                                                                         /*}}}*/
 521 // ServerState::HeaderLine - Process a header line                      /*{{{*/
 522 // ---------------------------------------------------------------------
 523 /* */
 524 bool ServerState::HeaderLine(string Line)
 525 {
 526    if (Line.empty() == true)
 527       return true;
 528
 529    // The http server might be trying to do something evil.
 530    if (Line.length() >= MAXLEN)
 531       return _error->Error(_("Got a single header line over %u chars"),MAXLEN);
 532
 533    string::size_type Pos = Line.find(' ');
 534    if (Pos == string::npos || Pos+1 > Line.length())
 535    {
 536       // Blah, some servers use "connection:closes", evil.
 537       Pos = Line.find(':');
 538       if (Pos == string::npos || Pos + 2 > Line.length())
 539          return _error->Error(_("Bad header line"));
 540       Pos++;
 541    }
 542
 543    // Parse off any trailing spaces between the : and the next word.
 544    string::size_type Pos2 = Pos;
 545    while (Pos2 < Line.length() && isspace(Line[Pos2]) != 0)
 546       Pos2++;
 547
 548    string Tag = string(Line,0,Pos);
 549    string Val = string(Line,Pos2);
 550
 551    if (stringcasecmp(Tag.c_str(),Tag.c_str()+4,"HTTP") == 0)
 552    {
 553       // Evil servers return no version
 554       if (Line[4] == '/')
 555       {
 556          if (sscanf(Line.c_str(),"HTTP/%u.%u %u%[^\n]",&Major,&Minor,
 557                     &Result,Code) != 4)
 558             return _error->Error(_("The HTTP server sent an invalid reply header"));
 559       }
 560       else
 561       {
 562          Major = 0;
 563          Minor = 9;
 564          if (sscanf(Line.c_str(),"HTTP %u%[^\n]",&Result,Code) != 2)
 565             return _error->Error(_("The HTTP server sent an invalid reply header"));
 566       }
 567
 568       /* Check the HTTP response header to get the default persistance
 569          state. */
 570       if (Major < 1)
 571          Persistent = false;
 572       else
 573       {
 574          if (Major == 1 && Minor <= 0)
 575             Persistent = false;
 576          else
 577             Persistent = true;
 578       }
 579
 580       return true;
 581    }
 582
 583    if (stringcasecmp(Tag,"Content-Length:") == 0)
 584    {
 585       if (Encoding == Closes)
 586          Encoding = Stream;
 587       HaveContent = true;
 588
 589       // The length is already set from the Content-Range header
 590       if (StartPos != 0)
 591          return true;
 592
 593       if (sscanf(Val.c_str(),"%lu",&Size) != 1)
 594          return _error->Error(_("The HTTP server sent an invalid Content-Length header"));
 595       return true;
 596    }
 597
 598    if (stringcasecmp(Tag,"Content-Type:") == 0)
 599    {
 600       HaveContent = true;
 601       return true;
 602    }
 603
 604    if (stringcasecmp(Tag,"Content-Range:") == 0)
 605    {
 606       HaveContent = true;
 607
 608       if (sscanf(Val.c_str(),"bytes %lu-%*u/%lu",&StartPos,&Size) != 2)
 609          return _error->Error(_("The HTTP server sent an invalid Content-Range header"));
 610       if ((unsigned)StartPos > Size)
 611          return _error->Error(_("This HTTP server has broken range support"));
 612       return true;
 613    }
 614
 615    if (stringcasecmp(Tag,"Transfer-Encoding:") == 0)
 616    {
 617       HaveContent = true;
 618       if (stringcasecmp(Val,"chunked") == 0)
 619          Encoding = Chunked;
 620       return true;
 621    }
 622
 623    if (stringcasecmp(Tag,"Connection:") == 0)
 624    {
 625       if (stringcasecmp(Val,"close") == 0)
 626          Persistent = false;
 627       if (stringcasecmp(Val,"keep-alive") == 0)
 628          Persistent = true;
 629       return true;
 630    }
 631
 632    if (stringcasecmp(Tag,"Last-Modified:") == 0)
 633    {
 634       if (StrToTime(Val,Date) == false)
 635          return _error->Error(_("Unknown date format"));
 636       return true;
 637    }
 638
 639    if (stringcasecmp(Tag,"Location:") == 0)
 640    {
 641       Location = Val;
 642       return true;
 643    }
 644
 645    return true;
 646 }
 647                                                                         /*}}}*/
 648
 649 // HttpMethod::SendReq - Send the HTTP request                          /*{{{*/
 650 // ---------------------------------------------------------------------
 651 /* This places the http request in the outbound buffer */
 652 void HttpMethod::SendReq(FetchItem *Itm,CircleBuf &Out)
 653 {
 654    URI Uri = Itm->Uri;
 655
 656    // The HTTP server expects a hostname with a trailing :port
 657    char Buf[1000];
 658    string ProperHost = Uri.Host;
 659    if (Uri.Port != 0)
 660    {
 661       sprintf(Buf,":%u",Uri.Port);
 662       ProperHost += Buf;
 663    }
 664
 665    // Just in case.
 666    if (Itm->Uri.length() >= sizeof(Buf))
 667        abort();
 668
 669    /* Build the request. We include a keep-alive header only for non-proxy
 670       requests. This is to tweak old http/1.0 servers that do support keep-alive
 671       but not HTTP/1.1 automatic keep-alive. Doing this with a proxy server
 672       will glitch HTTP/1.0 proxies because they do not filter it out and
 673       pass it on, HTTP/1.1 says the connection should default to keep alive
 674       and we expect the proxy to do this */
 675    if (Proxy.empty() == true || Proxy.Host.empty())
 676       sprintf(Buf,"GET %s HTTP/1.1\r\nHost: %s\r\nConnection: keep-alive\r\n",
 677               QuoteString(Uri.Path,"~").c_str(),ProperHost.c_str());
 678    else
 679    {
 680       /* Generate a cache control header if necessary. We place a max
 681          cache age on index files, optionally set a no-cache directive
 682          and a no-store directive for archives. */
 683       sprintf(Buf,"GET %s HTTP/1.1\r\nHost: %s\r\n",
 684               Itm->Uri.c_str(),ProperHost.c_str());
 685    }
 686    // generate a cache control header (if needed)
 687    if (_config->FindB("Acquire::http::No-Cache",false) == true)
 688    {
 689       strcat(Buf,"Cache-Control: no-cache\r\nPragma: no-cache\r\n");
 690    }
 691    else
 692    {
 693       if (Itm->IndexFile == true)
 694       {
 695          sprintf(Buf+strlen(Buf),"Cache-Control: max-age=%u\r\n",
 696                  _config->FindI("Acquire::http::Max-Age",0));
 697       }
 698       else
 699       {
 700          if (_config->FindB("Acquire::http::No-Store",false) == true)
 701             strcat(Buf,"Cache-Control: no-store\r\n");
 702       }
 703    }
 704
 705
 706    string Req = Buf;
 707
 708    // Check for a partial file
 709    struct stat SBuf;
 710    if (stat(Itm->DestFile.c_str(),&SBuf) >= 0 && SBuf.st_size > 0)
 711    {
 712       // In this case we send an if-range query with a range header
 713       sprintf(Buf,"Range: bytes=%li-\r\nIf-Range: %s\r\n",(long)SBuf.st_size - 1,
 714               TimeRFC1123(SBuf.st_mtime).c_str());
 715       Req += Buf;
 716    }
 717    else
 718    {
 719       if (Itm->LastModified != 0)
 720       {
 721          sprintf(Buf,"If-Modified-Since: %s\r\n",TimeRFC1123(Itm->LastModified).c_str());
 722          Req += Buf;
 723       }
 724    }
 725
 726    if (Proxy.User.empty() == false || Proxy.Password.empty() == false)
 727       Req += string("Proxy-Authorization: Basic ") +
 728           Base64Encode(Proxy.User + ":" + Proxy.Password) + "\r\n";
 729
 730    maybe_add_auth (Uri, _config->FindFile("Dir::Etc::netrc"));
 731    if (Uri.User.empty() == false || Uri.Password.empty() == false)
 732    {
 733       Req += string("Authorization: Basic ") +
 734           Base64Encode(Uri.User + ":" + Uri.Password) + "\r\n";
 735    }
 736    Req += "User-Agent: " + _config->Find("Acquire::http::User-Agent",
 737                 "Debian APT-HTTP/1.3 ("VERSION")") + "\r\n\r\n";
 738
 739    if (Debug == true)
 740       cerr << Req << endl;
 741
 742    Out.Read(Req);
 743 }
 744                                                                         /*}}}*/
 745 // HttpMethod::Go - Run a single loop                                   /*{{{*/
 746 // ---------------------------------------------------------------------
 747 /* This runs the select loop over the server FDs, Output file FDs and
 748    stdin. */
 749 bool HttpMethod::Go(bool ToFile,ServerState *Srv)
 750 {
 751    // Server has closed the connection
 752    if (Srv->ServerFd == -1 && (Srv->In.WriteSpace() == false ||
 753                                ToFile == false))
 754       return false;
 755
 756    fd_set rfds,wfds;
 757    FD_ZERO(&rfds);
 758    FD_ZERO(&wfds);
 759
 760    /* Add the server. We only send more requests if the connection will
 761       be persisting */
 762    if (Srv->Out.WriteSpace() == true && Srv->ServerFd != -1
 763        && Srv->Persistent == true)
 764       FD_SET(Srv->ServerFd,&wfds);
 765    if (Srv->In.ReadSpace() == true && Srv->ServerFd != -1)
 766       FD_SET(Srv->ServerFd,&rfds);
 767
 768    // Add the file
 769    int FileFD = -1;
 770    if (File != 0)
 771       FileFD = File->Fd();
 772
 773    if (Srv->In.WriteSpace() == true && ToFile == true && FileFD != -1)
 774       FD_SET(FileFD,&wfds);
 775
 776    // Add stdin
 777    FD_SET(STDIN_FILENO,&rfds);
 778
 779    // Figure out the max fd
 780    int MaxFd = FileFD;
 781    if (MaxFd < Srv->ServerFd)
 782       MaxFd = Srv->ServerFd;
 783
 784    // Select
 785    struct timeval tv;
 786    tv.tv_sec = TimeOut;
 787    tv.tv_usec = 0;
 788    int Res = 0;
 789    if ((Res = select(MaxFd+1,&rfds,&wfds,0,&tv)) < 0)
 790    {
 791       if (errno == EINTR)
 792          return true;
 793       return _error->Errno("select",_("Select failed"));
 794    }
 795
 796    if (Res == 0)
 797    {
 798       _error->Error(_("Connection timed out"));
 799       return ServerDie(Srv);
 800    }
 801
 802    // Handle server IO
 803    if (Srv->ServerFd != -1 && FD_ISSET(Srv->ServerFd,&rfds))
 804    {
 805       errno = 0;
 806       if (Srv->In.Read(Srv->ServerFd) == false)
 807          return ServerDie(Srv);
 808    }
 809
 810    if (Srv->ServerFd != -1 && FD_ISSET(Srv->ServerFd,&wfds))
 811    {
 812       errno = 0;
 813       if (Srv->Out.Write(Srv->ServerFd) == false)
 814          return ServerDie(Srv);
 815    }
 816
 817    // Send data to the file
 818    if (FileFD != -1 && FD_ISSET(FileFD,&wfds))
 819    {
 820       if (Srv->In.Write(FileFD) == false)
 821          return _error->Errno("write",_("Error writing to output file"));
 822    }
 823
 824    // Handle commands from APT
 825    if (FD_ISSET(STDIN_FILENO,&rfds))
 826    {
 827       if (Run(true) != -1)
 828          exit(100);
 829    }
 830
 831    return true;
 832 }
 833                                                                         /*}}}*/
 834 // HttpMethod::Flush - Dump the buffer into the file                    /*{{{*/
 835 // ---------------------------------------------------------------------
 836 /* This takes the current input buffer from the Server FD and writes it
 837    into the file */
 838 bool HttpMethod::Flush(ServerState *Srv)
 839 {
 840    if (File != 0)
 841    {
 842       // on GNU/kFreeBSD, apt dies on /dev/null because non-blocking
 843       // can't be set
 844       if (File->Name() != "/dev/null")
 845          SetNonBlock(File->Fd(),false);
 846       if (Srv->In.WriteSpace() == false)
 847          return true;
 848
 849       while (Srv->In.WriteSpace() == true)
 850       {
 851          if (Srv->In.Write(File->Fd()) == false)
 852             return _error->Errno("write",_("Error writing to file"));
 853          if (Srv->In.IsLimit() == true)
 854             return true;
 855       }
 856
 857       if (Srv->In.IsLimit() == true || Srv->Encoding == ServerState::Closes)
 858          return true;
 859    }
 860    return false;
 861 }
 862                                                                         /*}}}*/
 863 // HttpMethod::ServerDie - The server has closed the connection.        /*{{{*/
 864 // ---------------------------------------------------------------------
 865 /* */
 866 bool HttpMethod::ServerDie(ServerState *Srv)
 867 {
 868    unsigned int LErrno = errno;
 869
 870    // Dump the buffer to the file
 871    if (Srv->State == ServerState::Data)
 872    {
 873       // on GNU/kFreeBSD, apt dies on /dev/null because non-blocking
 874       // can't be set
 875       if (File->Name() != "/dev/null")
 876          SetNonBlock(File->Fd(),false);
 877       while (Srv->In.WriteSpace() == true)
 878       {
 879          if (Srv->In.Write(File->Fd()) == false)
 880             return _error->Errno("write",_("Error writing to the file"));
 881
 882          // Done
 883          if (Srv->In.IsLimit() == true)
 884             return true;
 885       }
 886    }
 887
 888    // See if this is because the server finished the data stream
 889    if (Srv->In.IsLimit() == false && Srv->State != ServerState::Header &&
 890        Srv->Encoding != ServerState::Closes)
 891    {
 892       Srv->Close();
 893       if (LErrno == 0)
 894          return _error->Error(_("Error reading from server. Remote end closed connection"));
 895       errno = LErrno;
 896       return _error->Errno("read",_("Error reading from server"));
 897    }
 898    else
 899    {
 900       Srv->In.Limit(-1);
 901
 902       // Nothing left in the buffer
 903       if (Srv->In.WriteSpace() == false)
 904          return false;
 905
 906       // We may have got multiple responses back in one packet..
 907       Srv->Close();
 908       return true;
 909    }
 910
 911    return false;
 912 }
 913                                                                         /*}}}*/
 914 // HttpMethod::DealWithHeaders - Handle the retrieved header data       /*{{{*/
 915 // ---------------------------------------------------------------------
 916 /* We look at the header data we got back from the server and decide what
 917    to do. Returns
 918      0 - File is open,
 919      1 - IMS hit
 920      3 - Unrecoverable error
 921      4 - Error with error content page
 922      5 - Unrecoverable non-server error (close the connection)
 923      6 - Try again with a new or changed URI
 924  */
 925 int HttpMethod::DealWithHeaders(FetchResult &Res,ServerState *Srv)
 926 {
 927    // Not Modified
 928    if (Srv->Result == 304)
 929    {
 930       unlink(Queue->DestFile.c_str());
 931       Res.IMSHit = true;
 932       Res.LastModified = Queue->LastModified;
 933       return 1;
 934    }
 935
 936    /* Redirect
 937     *
 938     * Note that it is only OK for us to treat all redirection the same
 939     * because we *always* use GET, not other HTTP methods.  There are
 940     * three redirection codes for which it is not appropriate that we
 941     * redirect.  Pass on those codes so the error handling kicks in.
 942     */
 943    if (AllowRedirect
 944        && (Srv->Result > 300 && Srv->Result < 400)
 945        && (Srv->Result != 300       // Multiple Choices
 946            && Srv->Result != 304    // Not Modified
 947            && Srv->Result != 306))  // (Not part of HTTP/1.1, reserved)
 948    {
 949       if (!Srv->Location.empty())
 950       {
 951          NextURI = Srv->Location;
 952          return 6;
 953       }
 954       /* else pass through for error message */
 955    }
 956
 957    /* We have a reply we dont handle. This should indicate a perm server
 958       failure */
 959    if (Srv->Result < 200 || Srv->Result >= 300)
 960    {
 961       _error->Error("%u %s",Srv->Result,Srv->Code);
 962       if (Srv->HaveContent == true)
 963          return 4;
 964       return 3;
 965    }
 966
 967    // This is some sort of 2xx 'data follows' reply
 968    Res.LastModified = Srv->Date;
 969    Res.Size = Srv->Size;
 970
 971    // Open the file
 972    delete File;
 973    File = new FileFd(Queue->DestFile,FileFd::WriteAny);
 974    if (_error->PendingError() == true)
 975       return 5;
 976
 977    FailFile = Queue->DestFile;
 978    FailFile.c_str();   // Make sure we dont do a malloc in the signal handler
 979    FailFd = File->Fd();
 980    FailTime = Srv->Date;
 981
 982    // Set the expected size
 983    if (Srv->StartPos >= 0)
 984    {
 985       Res.ResumePoint = Srv->StartPos;
 986       if (ftruncate(File->Fd(),Srv->StartPos) < 0)
 987          _error->Errno("ftruncate", _("Failed to truncate file"));
 988    }
 989
 990    // Set the start point
 991    lseek(File->Fd(),0,SEEK_END);
 992
 993    delete Srv->In.Hash;
 994    Srv->In.Hash = new Hashes;
 995
 996    // Fill the Hash if the file is non-empty (resume)
 997    if (Srv->StartPos > 0)
 998    {
 999       lseek(File->Fd(),0,SEEK_SET);
1000       if (Srv->In.Hash->AddFD(File->Fd(),Srv->StartPos) == false)
1001       {
1002          _error->Errno("read",_("Problem hashing file"));
1003          return 5;
1004       }
1005       lseek(File->Fd(),0,SEEK_END);
1006    }
1007
1008    SetNonBlock(File->Fd(),true);
1009    return 0;
1010 }
1011                                                                         /*}}}*/
1012 // HttpMethod::SigTerm - Handle a fatal signal                          /*{{{*/
1013 // ---------------------------------------------------------------------
1014 /* This closes and timestamps the open file. This is neccessary to get
1015    resume behavoir on user abort */
1016 void HttpMethod::SigTerm(int)
1017 {
1018    if (FailFd == -1)
1019       _exit(100);
1020    close(FailFd);
1021
1022    // Timestamp
1023    struct utimbuf UBuf;
1024    UBuf.actime = FailTime;
1025    UBuf.modtime = FailTime;
1026    utime(FailFile.c_str(),&UBuf);
1027
1028    _exit(100);
1029 }
1030                                                                         /*}}}*/
1031 // HttpMethod::Fetch - Fetch an item                                    /*{{{*/
1032 // ---------------------------------------------------------------------
1033 /* This adds an item to the pipeline. We keep the pipeline at a fixed
1034    depth. */
1035 bool HttpMethod::Fetch(FetchItem *)
1036 {
1037    if (Server == 0)
1038       return true;
1039
1040    // Queue the requests
1041    int Depth = -1;
1042    for (FetchItem *I = Queue; I != 0 && Depth < (signed)PipelineDepth;
1043         I = I->Next, Depth++)
1044    {
1045       // If pipelining is disabled, we only queue 1 request
1046       if (Server->Pipeline == false && Depth >= 0)
1047          break;
1048
1049       // Make sure we stick with the same server
1050       if (Server->Comp(I->Uri) == false)
1051          break;
1052       if (QueueBack == I)
1053       {
1054          QueueBack = I->Next;
1055          SendReq(I,Server->Out);
1056          continue;
1057       }
1058    }
1059
1060    return true;
1061 };
1062                                                                         /*}}}*/
1063 // HttpMethod::Configuration - Handle a configuration message           /*{{{*/
1064 // ---------------------------------------------------------------------
1065 /* We stash the desired pipeline depth */
1066 bool HttpMethod::Configuration(string Message)
1067 {
1068    if (pkgAcqMethod::Configuration(Message) == false)
1069       return false;
1070
1071    AllowRedirect = _config->FindB("Acquire::http::AllowRedirect",true);
1072    TimeOut = _config->FindI("Acquire::http::Timeout",TimeOut);
1073    PipelineDepth = _config->FindI("Acquire::http::Pipeline-Depth",
1074                                   PipelineDepth);
1075    Debug = _config->FindB("Debug::Acquire::http",false);
1076
1077    return true;
1078 }
1079                                                                         /*}}}*/
1080 // HttpMethod::Loop - Main loop                                         /*{{{*/
1081 // ---------------------------------------------------------------------
1082 /* */
1083 int HttpMethod::Loop()
1084 {
1085    typedef vector<string> StringVector;
1086    typedef vector<string>::iterator StringVectorIterator;
1087    map<string, StringVector> Redirected;
1088
1089    signal(SIGTERM,SigTerm);
1090    signal(SIGINT,SigTerm);
1091
1092    Server = 0;
1093
1094    int FailCounter = 0;
1095    while (1)
1096    {
1097       // We have no commands, wait for some to arrive
1098       if (Queue == 0)
1099       {
1100          if (WaitFd(STDIN_FILENO) == false)
1101             return 0;
1102       }
1103
1104       /* Run messages, we can accept 0 (no message) if we didn't
1105          do a WaitFd above.. Otherwise the FD is closed. */
1106       int Result = Run(true);
1107       if (Result != -1 && (Result != 0 || Queue == 0))
1108          return 100;
1109
1110       if (Queue == 0)
1111          continue;
1112
1113       // Connect to the server
1114       if (Server == 0 || Server->Comp(Queue->Uri) == false)
1115       {
1116          delete Server;
1117          Server = new ServerState(Queue->Uri,this);
1118       }
1119       /* If the server has explicitly said this is the last connection
1120          then we pre-emptively shut down the pipeline and tear down
1121          the connection. This will speed up HTTP/1.0 servers a tad
1122          since we don't have to wait for the close sequence to
1123          complete */
1124       if (Server->Persistent == false)
1125          Server->Close();
1126
1127       // Reset the pipeline
1128       if (Server->ServerFd == -1)
1129          QueueBack = Queue;
1130
1131       // Connnect to the host
1132       if (Server->Open() == false)
1133       {
1134          Fail(true);
1135          delete Server;
1136          Server = 0;
1137          continue;
1138       }
1139
1140       // Fill the pipeline.
1141       Fetch(0);
1142
1143       // Fetch the next URL header data from the server.
1144       switch (Server->RunHeaders())
1145       {
1146          case 0:
1147          break;
1148
1149          // The header data is bad
1150          case 2:
1151          {
1152             _error->Error(_("Bad header data"));
1153             Fail(true);
1154             RotateDNS();
1155             continue;
1156          }
1157
1158          // The server closed a connection during the header get..
1159          default:
1160          case 1:
1161          {
1162             FailCounter++;
1163             _error->Discard();
1164             Server->Close();
1165             Server->Pipeline = false;
1166
1167             if (FailCounter >= 2)
1168             {
1169                Fail(_("Connection failed"),true);
1170                FailCounter = 0;
1171             }
1172
1173             RotateDNS();
1174             continue;
1175          }
1176       };
1177
1178       // Decide what to do.
1179       FetchResult Res;
1180       Res.Filename = Queue->DestFile;
1181       switch (DealWithHeaders(Res,Server))
1182       {
1183          // Ok, the file is Open
1184          case 0:
1185          {
1186             URIStart(Res);
1187
1188             // Run the data
1189             bool Result =  Server->RunData();
1190
1191             /* If the server is sending back sizeless responses then fill in
1192                the size now */
1193             if (Res.Size == 0)
1194                Res.Size = File->Size();
1195
1196             // Close the file, destroy the FD object and timestamp it
1197             FailFd = -1;
1198             delete File;
1199             File = 0;
1200
1201             // Timestamp
1202             struct utimbuf UBuf;
1203             time(&UBuf.actime);
1204             UBuf.actime = Server->Date;
1205             UBuf.modtime = Server->Date;
1206             utime(Queue->DestFile.c_str(),&UBuf);
1207
1208             // Send status to APT
1209             if (Result == true)
1210             {
1211                Res.TakeHashes(*Server->In.Hash);
1212                URIDone(Res);
1213             }
1214             else
1215             {
1216                if (Server->ServerFd == -1)
1217                {
1218                   FailCounter++;
1219                   _error->Discard();
1220                   Server->Close();
1221
1222                   if (FailCounter >= 2)
1223                   {
1224                      Fail(_("Connection failed"),true);
1225                      FailCounter = 0;
1226                   }
1227
1228                   QueueBack = Queue;
1229                }
1230                else
1231                   Fail(true);
1232             }
1233             break;
1234          }
1235
1236          // IMS hit
1237          case 1:
1238          {
1239             URIDone(Res);
1240             break;
1241          }
1242
1243          // Hard server error, not found or something
1244          case 3:
1245          {
1246             Fail();
1247             break;
1248          }
1249
1250          // Hard internal error, kill the connection and fail
1251          case 5:
1252          {
1253             delete File;
1254             File = 0;
1255
1256             Fail();
1257             RotateDNS();
1258             Server->Close();
1259             break;
1260          }
1261
1262          // We need to flush the data, the header is like a 404 w/ error text
1263          case 4:
1264          {
1265             Fail();
1266
1267             // Send to content to dev/null
1268             File = new FileFd("/dev/null",FileFd::WriteExists);
1269             Server->RunData();
1270             delete File;
1271             File = 0;
1272             break;
1273          }
1274
1275          // Try again with a new URL
1276          case 6:
1277          {
1278             // Clear rest of response if there is content
1279             if (Server->HaveContent)
1280             {
1281                File = new FileFd("/dev/null",FileFd::WriteExists);
1282                Server->RunData();
1283                delete File;
1284                File = 0;
1285             }
1286
1287             /* Detect redirect loops.  No more redirects are allowed
1288                after the same URI is seen twice in a queue item. */
1289             StringVector &R = Redirected[Queue->DestFile];
1290             bool StopRedirects = false;
1291             if (R.size() == 0)
1292                R.push_back(Queue->Uri);
1293             else if (R[0] == "STOP" || R.size() > 10)
1294                StopRedirects = true;
1295             else
1296             {
1297                for (StringVectorIterator I = R.begin(); I != R.end(); I++)
1298                   if (Queue->Uri == *I)
1299                   {
1300                      R[0] = "STOP";
1301                      break;
1302                   }
1303
1304                R.push_back(Queue->Uri);
1305             }
1306
1307             if (StopRedirects == false)
1308                Redirect(NextURI);
1309             else
1310                Fail();
1311
1312             break;
1313          }
1314
1315          default:
1316          Fail(_("Internal error"));
1317          break;
1318       }
1319
1320       FailCounter = 0;
1321    }
1322
1323    return 0;
1324 }
1325                                                                         /*}}}*/
1326
1327 int main()
1328 {
1329    setlocale(LC_ALL, "");
1330    // ignore SIGPIPE, this can happen on write() if the socket
1331    // closes the connection (this is dealt with via ServerDie())
1332    signal(SIGPIPE, SIG_IGN);
1333
1334    HttpMethod Mth;
1335    return Mth.Loop();
1336 }
1337
1338