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