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