test/interactive-helper/aptwebserver.cc

   1 #include <config.h>
   2
   3 #include <apt-pkg/strutl.h>
   4 #include <apt-pkg/fileutl.h>
   5 #include <apt-pkg/error.h>
   6 #include <apt-pkg/cmndline.h>
   7 #include <apt-pkg/configuration.h>
   8 #include <apt-pkg/init.h>
   9
  10 #include <vector>
  11 #include <string>
  12 #include <list>
  13 #include <sstream>
  14
  15 #include <sys/socket.h>
  16 #include <sys/types.h>
  17 #include <sys/stat.h>
  18 #include <netinet/in.h>
  19 #include <unistd.h>
  20 #include <errno.h>
  21 #include <time.h>
  22 #include <stdlib.h>
  23 #include <dirent.h>
  24 #include <signal.h>
  25
  26 char const * const httpcodeToStr(int const httpcode)                    /*{{{*/
  27 {
  28    switch (httpcode)
  29    {
  30       // Informational 1xx
  31       case 100: return "100 Continue";
  32       case 101: return "101 Switching Protocols";
  33       // Successful 2xx
  34       case 200: return "200 OK";
  35       case 201: return "201 Created";
  36       case 202: return "202 Accepted";
  37       case 203: return "203 Non-Authoritative Information";
  38       case 204: return "204 No Content";
  39       case 205: return "205 Reset Content";
  40       case 206: return "206 Partial Content";
  41       // Redirections 3xx
  42       case 300: return "300 Multiple Choices";
  43       case 301: return "301 Moved Permanently";
  44       case 302: return "302 Found";
  45       case 303: return "303 See Other";
  46       case 304: return "304 Not Modified";
  47       case 305: return "304 Use Proxy";
  48       case 307: return "307 Temporary Redirect";
  49       // Client errors 4xx
  50       case 400: return "400 Bad Request";
  51       case 401: return "401 Unauthorized";
  52       case 402: return "402 Payment Required";
  53       case 403: return "403 Forbidden";
  54       case 404: return "404 Not Found";
  55       case 405: return "405 Method Not Allowed";
  56       case 406: return "406 Not Acceptable";
  57       case 407: return "407 Proxy Authentication Required";
  58       case 408: return "408 Request Time-out";
  59       case 409: return "409 Conflict";
  60       case 410: return "410 Gone";
  61       case 411: return "411 Length Required";
  62       case 412: return "412 Precondition Failed";
  63       case 413: return "413 Request Entity Too Large";
  64       case 414: return "414 Request-URI Too Large";
  65       case 415: return "415 Unsupported Media Type";
  66       case 416: return "416 Requested range not satisfiable";
  67       case 417: return "417 Expectation Failed";
  68       case 418: return "418 I'm a teapot";
  69       // Server error 5xx
  70       case 500: return "500 Internal Server Error";
  71       case 501: return "501 Not Implemented";
  72       case 502: return "502 Bad Gateway";
  73       case 503: return "503 Service Unavailable";
  74       case 504: return "504 Gateway Time-out";
  75       case 505: return "505 HTTP Version not supported";
  76    }
  77    return NULL;
  78 }
  79                                                                         /*}}}*/
  80 void addFileHeaders(std::list<std::string> &headers, FileFd &data)      /*{{{*/
  81 {
  82    std::ostringstream contentlength;
  83    contentlength << "Content-Length: " << data.FileSize();
  84    headers.push_back(contentlength.str());
  85
  86    std::string lastmodified("Last-Modified: ");
  87    lastmodified.append(TimeRFC1123(data.ModificationTime()));
  88    headers.push_back(lastmodified);
  89 }
  90                                                                         /*}}}*/
  91 void addDataHeaders(std::list<std::string> &headers, std::string &data) /*{{{*/
  92 {
  93    std::ostringstream contentlength;
  94    contentlength << "Content-Length: " << data.size();
  95    headers.push_back(contentlength.str());
  96 }
  97                                                                         /*}}}*/
  98 bool sendHead(int const client, int const httpcode, std::list<std::string> &headers)/*{{{*/
  99 {
 100    std::string response("HTTP/1.1 ");
 101    response.append(httpcodeToStr(httpcode));
 102    headers.push_front(response);
 103
 104    headers.push_back("Server: APT webserver");
 105
 106    std::string date("Date: ");
 107    date.append(TimeRFC1123(time(NULL)));
 108    headers.push_back(date);
 109
 110    std::clog << ">>> RESPONSE >>>" << std::endl;
 111    bool Success = true;
 112    for (std::list<std::string>::const_iterator h = headers.begin();
 113         Success == true && h != headers.end(); ++h)
 114    {
 115       Success &= FileFd::Write(client, h->c_str(), h->size());
 116       if (Success == true)
 117          Success &= FileFd::Write(client, "\r\n", 2);
 118       std::clog << *h << std::endl;
 119    }
 120    if (Success == true)
 121       Success &= FileFd::Write(client, "\r\n", 2);
 122    std::clog << "<<<<<<<<<<<<<<<<" << std::endl;
 123    return Success;
 124 }
 125                                                                         /*}}}*/
 126 bool sendFile(int const client, FileFd &data)                           /*{{{*/
 127 {
 128    bool Success = true;
 129    char buffer[500];
 130    unsigned long long actual = 0;
 131    while ((Success &= data.Read(buffer, sizeof(buffer), &actual)) == true)
 132    {
 133       if (actual == 0)
 134          break;
 135       if (Success == true)
 136          Success &= FileFd::Write(client, buffer, actual);
 137    }
 138    if (Success == true)
 139       Success &= FileFd::Write(client, "\r\n", 2);
 140    return Success;
 141 }
 142                                                                         /*}}}*/
 143 bool sendData(int const client, std::string const &data)                /*{{{*/
 144 {
 145    bool Success = true;
 146    Success &= FileFd::Write(client, data.c_str(), data.size());
 147    if (Success == true)
 148       Success &= FileFd::Write(client, "\r\n", 2);
 149    return Success;
 150 }
 151                                                                         /*}}}*/
 152 void sendError(int const client, int const httpcode, std::string const &request,/*{{{*/
 153                bool content, std::string const &error = "")
 154 {
 155    std::list<std::string> headers;
 156    std::string response("<html><head><title>");
 157    response.append(httpcodeToStr(httpcode)).append("</title></head>");
 158    response.append("<body><h1>").append(httpcodeToStr(httpcode)).append("</h1>");
 159    if (error.empty() == false)
 160       response.append("<p><em>Error</em>: ").append(error).append("</p>");
 161    response.append("This error is a result of the request: <pre>");
 162    response.append(request).append("</pre></body></html>");
 163    addDataHeaders(headers, response);
 164    sendHead(client, httpcode, headers);
 165    if (content == true)
 166       sendData(client, response);
 167 }
 168                                                                         /*}}}*/
 169 void sendRedirect(int const client, int const httpcode, std::string const &uri,/*{{{*/
 170                   std::string const &request, bool content)
 171 {
 172    std::list<std::string> headers;
 173    std::string response("<html><head><title>");
 174    response.append(httpcodeToStr(httpcode)).append("</title></head>");
 175    response.append("<body><h1>").append(httpcodeToStr(httpcode)).append("</h1");
 176    response.append("<p>You should be redirected to <em>").append(uri).append("</em></p>");
 177    response.append("This page is a result of the request: <pre>");
 178    response.append(request).append("</pre></body></html>");
 179    addDataHeaders(headers, response);
 180    std::string location("Location: ");
 181    if (strncmp(uri.c_str(), "http://", 7) != 0)
 182       location.append("http://").append(LookupTag(request, "Host")).append("/").append(uri);
 183    else
 184       location.append(uri);
 185    headers.push_back(location);
 186    sendHead(client, httpcode, headers);
 187    if (content == true)
 188       sendData(client, response);
 189 }
 190                                                                         /*}}}*/
 191 int filter_hidden_files(const struct dirent *a)                         /*{{{*/
 192 {
 193    if (a->d_name[0] == '.')
 194       return 0;
 195 #ifdef _DIRENT_HAVE_D_TYPE
 196    // if we have the d_type check that only files and dirs will be included
 197    if (a->d_type != DT_UNKNOWN &&
 198        a->d_type != DT_REG &&
 199        a->d_type != DT_LNK && // this includes links to regular files
 200        a->d_type != DT_DIR)
 201       return 0;
 202 #endif
 203    return 1;
 204 }
 205 int grouped_alpha_case_sort(const struct dirent **a, const struct dirent **b) {
 206 #ifdef _DIRENT_HAVE_D_TYPE
 207    if ((*a)->d_type == DT_DIR && (*b)->d_type == DT_DIR);
 208    else if ((*a)->d_type == DT_DIR && (*b)->d_type == DT_REG)
 209       return -1;
 210    else if ((*b)->d_type == DT_DIR && (*a)->d_type == DT_REG)
 211       return 1;
 212    else
 213 #endif
 214    {
 215       struct stat f_prop; //File's property
 216       stat((*a)->d_name, &f_prop);
 217       int const amode = f_prop.st_mode;
 218       stat((*b)->d_name, &f_prop);
 219       int const bmode = f_prop.st_mode;
 220       if (S_ISDIR(amode) && S_ISDIR(bmode));
 221       else if (S_ISDIR(amode))
 222          return -1;
 223       else if (S_ISDIR(bmode))
 224          return 1;
 225    }
 226    return strcasecmp((*a)->d_name, (*b)->d_name);
 227 }
 228                                                                         /*}}}*/
 229 void sendDirectoryListing(int const client, std::string const &dir,     /*{{{*/
 230                           std::string const &request, bool content)
 231 {
 232    std::list<std::string> headers;
 233    std::ostringstream listing;
 234
 235    struct dirent **namelist;
 236    int const counter = scandir(dir.c_str(), &namelist, filter_hidden_files, grouped_alpha_case_sort);
 237    if (counter == -1)
 238    {
 239       sendError(client, 500, request, content);
 240       return;
 241    }
 242
 243    listing << "<html><head><title>Index of " << dir << "</title>"
 244            << "<style type=\"text/css\"><!-- td {padding: 0.02em 0.5em 0.02em 0.5em;}"
 245            << "tr:nth-child(even){background-color:#dfdfdf;}"
 246            << "h1, td:nth-child(3){text-align:center;}"
 247            << "table {margin-left:auto;margin-right:auto;} --></style>"
 248            << "</head>" << std::endl
 249            << "<body><h1>Index of " << dir << "</h1>" << std::endl
 250            << "<table><tr><th>#</th><th>Name</th><th>Size</th><th>Last-Modified</th></tr>" << std::endl;
 251    if (dir != ".")
 252       listing << "<tr><td>d</td><td><a href=\"..\">Parent Directory</a></td><td>-</td><td>-</td></tr>";
 253    for (int i = 0; i < counter; ++i) {
 254       struct stat fs;
 255       std::string filename(dir);
 256       filename.append("/").append(namelist[i]->d_name);
 257       stat(filename.c_str(), &fs);
 258       if (S_ISDIR(fs.st_mode))
 259       {
 260          listing << "<tr><td>d</td>"
 261                  << "<td><a href=\"" << namelist[i]->d_name << "/\">" << namelist[i]->d_name << "</a></td>"
 262                  << "<td>-</td>";
 263       }
 264       else
 265       {
 266          listing << "<tr><td>f</td>"
 267                  << "<td><a href=\"" << namelist[i]->d_name << "\">" << namelist[i]->d_name << "</a></td>"
 268                  << "<td>" << SizeToStr(fs.st_size) << "B</td>";
 269       }
 270       listing << "<td>" << TimeRFC1123(fs.st_mtime) << "</td></tr>" << std::endl;
 271    }
 272    listing << "</table></body></html>" << std::endl;
 273
 274    std::string response(listing.str());
 275    addDataHeaders(headers, response);
 276    sendHead(client, 200, headers);
 277    if (content == true)
 278       sendData(client, response);
 279 }
 280                                                                         /*}}}*/
 281 bool parseFirstLine(int const client, std::string const &request,       /*{{{*/
 282                     std::string &filename, bool &sendContent,
 283                     bool &closeConnection)
 284 {
 285    if (strncmp(request.c_str(), "HEAD ", 5) == 0)
 286       sendContent = false;
 287    if (strncmp(request.c_str(), "GET ", 4) != 0)
 288    {
 289       sendError(client, 501, request, true);
 290       return false;
 291    }
 292
 293    size_t const lineend = request.find('\n');
 294    size_t filestart = request.find(' ');
 295    for (; request[filestart] == ' '; ++filestart);
 296    size_t fileend = request.rfind(' ', lineend);
 297    if (lineend == std::string::npos || filestart == std::string::npos ||
 298          fileend == std::string::npos || filestart == fileend)
 299    {
 300       sendError(client, 500, request, sendContent, "Filename can't be extracted");
 301       return false;
 302    }
 303
 304    size_t httpstart = fileend;
 305    for (; request[httpstart] == ' '; ++httpstart);
 306    if (strncmp(request.c_str() + httpstart, "HTTP/1.1\r", 9) == 0)
 307       closeConnection = strcasecmp(LookupTag(request, "Connection", "Keep-Alive").c_str(), "Keep-Alive") != 0;
 308    else if (strncmp(request.c_str() + httpstart, "HTTP/1.0\r", 9) == 0)
 309       closeConnection = strcasecmp(LookupTag(request, "Connection", "Keep-Alive").c_str(), "close") == 0;
 310    else
 311    {
 312       sendError(client, 500, request, sendContent, "Not a HTTP/1.{0,1} request");
 313       return false;
 314    }
 315
 316    filename = request.substr(filestart, fileend - filestart);
 317    if (filename.find(' ') != std::string::npos)
 318    {
 319       sendError(client, 500, request, sendContent, "Filename contains an unencoded space");
 320       return false;
 321    }
 322
 323    std::string host = LookupTag(request, "Host", "");
 324    if (host.empty() == true)
 325    {
 326       // RFC 2616 §14.23 requires Host
 327       sendError(client, 400, request, sendContent, "Host header is required");
 328       return false;
 329    }
 330    host = "http://" + host;
 331
 332    // Proxies require absolute uris, so this is a simple proxy-fake option
 333    std::string const absolute = _config->Find("aptwebserver::request::absolute", "uri,path");
 334    if (strncmp(host.c_str(), filename.c_str(), host.length()) == 0)
 335    {
 336       if (absolute.find("uri") == std::string::npos)
 337       {
 338          sendError(client, 400, request, sendContent, "Request is absoluteURI, but configured to not accept that");
 339          return false;
 340       }
 341       // strip the host from the request to make it an absolute path
 342       filename.erase(0, host.length());
 343    }
 344    else if (absolute.find("path") == std::string::npos)
 345    {
 346       sendError(client, 400, request, sendContent, "Request is absolutePath, but configured to not accept that");
 347       return false;
 348    }
 349    filename = DeQuoteString(filename);
 350
 351    // this is not a secure server, but at least prevent the obvious …
 352    if (filename.empty() == true || filename[0] != '/' ||
 353        strncmp(filename.c_str(), "//", 2) == 0 ||
 354        filename.find_first_of("\r\n\t\f\v") != std::string::npos ||
 355        filename.find("/../") != std::string::npos)
 356    {
 357       sendError(client, 400, request, sendContent, "Filename contains illegal character (sequence)");
 358       return false;
 359    }
 360
 361    // nuke the first character which is a / as we assured above
 362    filename.erase(0, 1);
 363    if (filename.empty() == true)
 364       filename = ".";
 365    return true;
 366 }
 367                                                                         /*}}}*/
 368 int main(int const argc, const char * argv[])
 369 {
 370    CommandLine::Args Args[] = {
 371       {0, "port", "aptwebserver::port", CommandLine::HasArg},
 372       {0, "request-absolute", "aptwebserver::request::absolute", CommandLine::HasArg},
 373       {'c',"config-file",0,CommandLine::ConfigFile},
 374       {'o',"option",0,CommandLine::ArbItem},
 375       {0,0,0,0}
 376    };
 377
 378    CommandLine CmdL(Args, _config);
 379    if(CmdL.Parse(argc,argv) == false)
 380    {
 381       _error->DumpErrors();
 382       exit(1);
 383    }
 384
 385    // create socket, bind and listen to it {{{
 386    // ignore SIGPIPE, this can happen on write() if the socket closes connection
 387    signal(SIGPIPE, SIG_IGN);
 388    int sock = socket(AF_INET6, SOCK_STREAM, 0);
 389    if(sock < 0)
 390    {
 391       _error->Errno("aptwerbserver", "Couldn't create socket");
 392       _error->DumpErrors(std::cerr);
 393       return 1;
 394    }
 395
 396    int const port = _config->FindI("aptwebserver::port", 8080);
 397
 398    // ensure that we accept all connections: v4 or v6
 399    int const iponly = 0;
 400    setsockopt(sock, IPPROTO_IPV6, IPV6_V6ONLY, &iponly, sizeof(iponly));
 401    // to not linger on an address
 402    int const enable = 1;
 403    setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, &enable, sizeof(enable));
 404
 405    struct sockaddr_in6 locAddr;
 406    memset(&locAddr, 0, sizeof(locAddr));
 407    locAddr.sin6_family = AF_INET6;
 408    locAddr.sin6_port = htons(port);
 409    locAddr.sin6_addr = in6addr_any;
 410
 411    if (bind(sock, (struct sockaddr*) &locAddr, sizeof(locAddr)) < 0)
 412    {
 413       _error->Errno("aptwerbserver", "Couldn't bind");
 414       _error->DumpErrors(std::cerr);
 415       return 2;
 416    }
 417
 418    FileFd pidfile;
 419    if (_config->FindB("aptwebserver::fork", false) == true)
 420    {
 421       std::string const pidfilename = _config->Find("aptwebserver::pidfile", "aptwebserver.pid");
 422       int const pidfilefd = GetLock(pidfilename);
 423       if (pidfilefd < 0 || pidfile.OpenDescriptor(pidfilefd, FileFd::WriteOnly) == false)
 424       {
 425          _error->Errno("aptwebserver", "Couldn't acquire lock on pidfile '%s'", pidfilename.c_str());
 426          _error->DumpErrors(std::cerr);
 427          return 3;
 428       }
 429
 430       pid_t child = fork();
 431       if (child < 0)
 432       {
 433          _error->Errno("aptwebserver", "Forking failed");
 434          _error->DumpErrors(std::cerr);
 435          return 4;
 436       }
 437       else if (child != 0)
 438       {
 439          // successfully forked: ready to serve!
 440          std::string pidcontent;
 441          strprintf(pidcontent, "%d", child);
 442          pidfile.Write(pidcontent.c_str(), pidcontent.size());
 443          if (_error->PendingError() == true)
 444          {
 445             _error->DumpErrors(std::cerr);
 446             return 5;
 447          }
 448          std::cout << "Successfully forked as " << child << std::endl;
 449          return 0;
 450       }
 451    }
 452
 453    std::clog << "Serving ANY file on port: " << port << std::endl;
 454
 455    listen(sock, 1);
 456    /*}}}*/
 457
 458    std::vector<std::string> messages;
 459    int client;
 460    while ((client = accept(sock, NULL, NULL)) != -1)
 461    {
 462       std::clog << "ACCEPT client " << client
 463                 << " on socket " << sock << std::endl;
 464
 465       while (ReadMessages(client, messages))
 466       {
 467          bool closeConnection = false;
 468          for (std::vector<std::string>::const_iterator m = messages.begin();
 469               m != messages.end() && closeConnection == false; ++m) {
 470             std::clog << ">>> REQUEST >>>>" << std::endl << *m
 471                       << std::endl << "<<<<<<<<<<<<<<<<" << std::endl;
 472             std::list<std::string> headers;
 473             std::string filename;
 474             bool sendContent = true;
 475             if (parseFirstLine(client, *m, filename, sendContent, closeConnection) == false)
 476                continue;
 477
 478             // string replacements in the requested filename
 479             ::Configuration::Item const *Replaces = _config->Tree("aptwebserver::redirect::replace");
 480             if (Replaces != NULL)
 481             {
 482                std::string redirect = "/" + filename;
 483                for (::Configuration::Item *I = Replaces->Child; I != NULL; I = I->Next)
 484                   redirect = SubstVar(redirect, I->Tag, I->Value);
 485                redirect.erase(0,1);
 486                if (redirect != filename)
 487                {
 488                   sendRedirect(client, 301, redirect, *m, sendContent);
 489                   continue;
 490                }
 491             }
 492
 493             ::Configuration::Item const *Overwrite = _config->Tree("aptwebserver::overwrite");
 494             if (Overwrite != NULL)
 495             {
 496                for (::Configuration::Item *I = Overwrite->Child; I != NULL; I = I->Next)
 497                {
 498                   regex_t *pattern = new regex_t;
 499                   int const res = regcomp(pattern, I->Tag.c_str(), REG_EXTENDED | REG_ICASE | REG_NOSUB);
 500                   if (res != 0)
 501                   {
 502                      char error[300];
 503                      regerror(res, pattern, error, sizeof(error));
 504                      sendError(client, 500, *m, sendContent, error);
 505                      continue;
 506                   }
 507                   if (regexec(pattern, filename.c_str(), 0, 0, 0) == 0)
 508                   {
 509                       filename = _config->Find("aptwebserver::overwrite::" + I->Tag + "::filename", filename);
 510                       if (filename[0] == '/')
 511                          filename.erase(0,1);
 512                       regfree(pattern);
 513                       break;
 514                   }
 515                   regfree(pattern);
 516                }
 517             }
 518
 519             // deal with the request
 520             if (RealFileExists(filename) == true)
 521             {
 522                FileFd data(filename, FileFd::ReadOnly);
 523                std::string condition = LookupTag(*m, "If-Modified-Since", "");
 524                if (condition.empty() == false)
 525                {
 526                   time_t cache;
 527                   if (RFC1123StrToTime(condition.c_str(), cache) == true &&
 528                         cache >= data.ModificationTime())
 529                   {
 530                      sendHead(client, 304, headers);
 531                      continue;
 532                   }
 533                }
 534
 535                addFileHeaders(headers, data);
 536                sendHead(client, 200, headers);
 537                if (sendContent == true)
 538                   sendFile(client, data);
 539             }
 540             else if (DirectoryExists(filename) == true)
 541             {
 542                if (filename == "." || filename[filename.length()-1] == '/')
 543                   sendDirectoryListing(client, filename, *m, sendContent);
 544                else
 545                   sendRedirect(client, 301, filename.append("/"), *m, sendContent);
 546             }
 547             else
 548                sendError(client, 404, *m, sendContent);
 549          }
 550          _error->DumpErrors(std::cerr);
 551          messages.clear();
 552          if (closeConnection == true)
 553             break;
 554       }
 555
 556       std::clog << "CLOSE client " << client
 557                 << " on socket " << sock << std::endl;
 558       close(client);
 559    }
 560    pidfile.Close();
 561
 562    return 0;
 563 }