liblightdm-qt/QLightDM/greeter.cpp

   1 /*
   2  * Copyright (C) 2010-2011 David Edmundson
   3  * Copyright (C) 2010-2011 Robert Ancell
   4  * Author: David Edmundson <kde@davidedmundson.co.uk>
   5  *
   6  * This library is free software; you can redistribute it and/or modify it under
   7  * the terms of the GNU Lesser General Public License as published by the Free
   8  * Software Foundation; either version 3 of the License, or (at your option) any
   9  * later version. See http://www.gnu.org/copyleft/lgpl.html the full text of the
  10  * license.
  11  */
  12
  13 #include "greeter.h"
  14
  15 #include "user.h"
  16 #include "sessionsmodel.h"
  17 #include "config.h"
  18
  19 #include <security/pam_appl.h>
  20
  21 #include <QtNetwork/QHostInfo> //needed for localHostName
  22 #include <QtCore/QDebug>
  23 #include <QtCore/QDir>
  24 #include <QtCore/QVariant>
  25 #include <QtCore/QSettings>
  26 #include <QtCore/QUrl>
  27 #include <QtCore/QFile>
  28 #include <QtCore/QHash>
  29 #include <QtCore/QSocketNotifier>
  30 #include <QtDBus/QDBusPendingReply>
  31 #include <QtDBus/QDBusInterface>
  32 #include <QtDBus/QDBusReply>
  33
  34 /* Messages from the greeter to the server */
  35 typedef enum
  36 {
  37     GREETER_MESSAGE_CONNECT = 0,
  38     GREETER_MESSAGE_LOGIN,
  39     GREETER_MESSAGE_LOGIN_AS_GUEST,
  40     GREETER_MESSAGE_CONTINUE_AUTHENTICATION,
  41     GREETER_MESSAGE_START_SESSION,
  42     GREETER_MESSAGE_CANCEL_AUTHENTICATION
  43 } GreeterMessage;
  44
  45 /* Messages from the server to the greeter */
  46 typedef enum
  47 {
  48     SERVER_MESSAGE_CONNECTED = 0,
  49     SERVER_MESSAGE_QUIT,
  50     SERVER_MESSAGE_PROMPT_AUTHENTICATION,
  51     SERVER_MESSAGE_END_AUTHENTICATION,
  52     SERVER_MESSAGE_SESSION_FAILED,
  53 } ServerMessage;
  54
  55 #define HEADER_SIZE 8
  56
  57 using namespace QLightDM;
  58
  59 class GreeterPrivate
  60 {
  61 public:
  62     SessionsModel *sessionsModel;
  63
  64     QDBusInterface* lightdmInterface;
  65     QDBusInterface* powerManagementInterface;
  66     QDBusInterface* consoleKitInterface;
  67
  68     QHash<QString, QString> hints;
  69
  70     int toServerFd;
  71     int fromServerFd;
  72     QSocketNotifier *n;
  73     char *readBuffer;
  74     int nRead;
  75     bool inAuthentication;
  76     bool isAuthenticated;
  77     QString authenticationUser;
  78     int authenticateSequenceNumber;
  79     bool cancellingAuthentication;
  80 };
  81
  82
  83 Greeter::Greeter(QObject *parent) :
  84     QObject(parent),
  85     d(new GreeterPrivate)
  86 {
  87     d->readBuffer = (char *)malloc (HEADER_SIZE);
  88     d->nRead = 0;
  89     d->sessionsModel = new SessionsModel(this);
  90     d->authenticateSequenceNumber = 0;
  91 }
  92
  93 Greeter::~Greeter()
  94 {
  95     delete d->readBuffer;
  96     delete d;
  97 }
  98
  99 static int intLength()
 100 {
 101     return 4;
 102 }
 103
 104 static int stringLength(QString value)
 105 {
 106     QByteArray a = value.toUtf8();
 107     return intLength() + a.size();
 108 }
 109
 110 void Greeter::writeInt(int value)
 111 {
 112     char buffer[4];
 113     buffer[0] = value >> 24;
 114     buffer[1] = (value >> 16) & 0xFF;
 115     buffer[2] = (value >> 8) & 0xFF;
 116     buffer[3] = value & 0xFF;
 117     if (write(d->toServerFd, buffer, intLength()) != intLength()) {
 118         qDebug() << "Error writing to server";
 119     }
 120 }
 121
 122 void Greeter::writeString(QString value)
 123 {
 124     QByteArray a = value.toUtf8();
 125     writeInt(a.size());
 126     if (write(d->toServerFd, a.data(), a.size()) != a.size()) {
 127         qDebug() << "Error writing to server";
 128     }
 129 }
 130
 131 void Greeter::writeHeader(int id, int length)
 132 {
 133     writeInt(id);
 134     writeInt(length);
 135 }
 136
 137 void Greeter::flush()
 138 {
 139     fsync(d->toServerFd);
 140 }
 141
 142 int Greeter::getPacketLength()
 143 {
 144     int offset = intLength();
 145     return readInt(&offset);
 146 }
 147
 148 int Greeter::readInt(int *offset)
 149 {
 150     if(d->nRead - *offset < intLength()) {
 151         qDebug() << "Not enough space for int, need " << intLength() << ", got " << (d->nRead - *offset);
 152         return 0;
 153     }
 154
 155     char *buffer = d->readBuffer + *offset;
 156     int value = buffer[0] << 24 | buffer[1] << 16 | buffer[2] << 8 | buffer[3];
 157     *offset += intLength();
 158     return value;
 159 }
 160
 161 QString Greeter::readString(int *offset)
 162 {
 163     int length = readInt(offset);
 164     if(d->nRead - *offset < length) {
 165         qDebug() << "Not enough space for string, need " << length << ", got " << (d->nRead - *offset);
 166         return "";
 167     }
 168     char *start = d->readBuffer + *offset;
 169     *offset += length;
 170     return QString::fromUtf8(start, length);
 171 }
 172
 173 void Greeter::connectToServer()
 174 {
 175     QDBusConnection busType = QDBusConnection::systemBus();
 176     QString ldmBus(qgetenv("LDM_BUS"));
 177     if(ldmBus == QLatin1String("SESSION")) {
 178         busType = QDBusConnection::sessionBus();
 179     }
 180
 181     d->lightdmInterface = new QDBusInterface("org.freedesktop.DisplayManager", "/org/freedesktop/DisplayManager", "org.freedesktop.DisplayManager", busType);
 182     d->powerManagementInterface = new QDBusInterface("org.freedesktop.PowerManagement","/org/freedesktop/PowerManagement", "org.freedesktop.PowerManagement");
 183     d->consoleKitInterface = new QDBusInterface("org.freedesktop.ConsoleKit", "/org/freedesktop/ConsoleKit/Manager", "org.freedesktop.ConsoleKit");
 184
 185     char* fd = getenv("LIGHTDM_TO_SERVER_FD");
 186     if(!fd) {
 187        qDebug() << "No LIGHTDM_TO_SERVER_FD environment variable";
 188        return;
 189     }
 190     d->toServerFd = atoi(fd);
 191
 192     qDebug() << "***connecting to server";
 193     QFile toServer;
 194     qDebug() << toServer.open(d->toServerFd, QIODevice::WriteOnly);
 195
 196     fd = getenv("LIGHTDM_FROM_SERVER_FD");
 197     if(!fd) {
 198        qDebug() << "No LIGHTDM_FROM_SERVER_FD environment variable";
 199        return;
 200     }
 201     d->fromServerFd = atoi(fd);
 202
 203     d->n = new QSocketNotifier(d->fromServerFd, QSocketNotifier::Read);
 204     connect(d->n, SIGNAL(activated(int)), this, SLOT(onRead(int)));
 205
 206     qDebug() << "Connecting to display manager...";
 207     writeHeader(GREETER_MESSAGE_CONNECT, stringLength(VERSION));
 208     writeString(VERSION);
 209     flush();
 210 }
 211
 212 void Greeter::login(const QString &username)
 213 {
 214     d->inAuthentication = true;
 215     d->isAuthenticated = false;
 216     d->cancellingAuthentication = false;
 217     d->authenticationUser = username;
 218     qDebug() << "Starting authentication for user " << username << "...";
 219     writeHeader(GREETER_MESSAGE_LOGIN, intLength() + stringLength(username));
 220     d->authenticateSequenceNumber++;
 221     writeInt(d->authenticateSequenceNumber);
 222     writeString(username);
 223     flush();
 224 }
 225
 226 void Greeter::loginAsGuest()
 227 {
 228     d->authenticateSequenceNumber++;
 229     d->inAuthentication = true;
 230     d->isAuthenticated = false;
 231     d->cancellingAuthentication = false;
 232     d->authenticationUser = "";
 233     qDebug() << "Starting authentication for guest account";
 234     writeHeader(GREETER_MESSAGE_LOGIN_AS_GUEST, intLength());
 235     writeInt(d->authenticateSequenceNumber);
 236     flush();
 237 }
 238
 239 void Greeter::respond(const QString &response)
 240 {
 241     qDebug() << "Providing response to display manager";
 242     writeHeader(GREETER_MESSAGE_CONTINUE_AUTHENTICATION, intLength() + stringLength(response));
 243     // FIXME: Could be multiple response required
 244     writeInt(1);
 245     writeString(response);
 246     flush();
 247 }
 248
 249 void Greeter::cancelAuthentication()
 250 {
 251     qDebug() << "Cancelling authentication";
 252     d->cancellingAuthentication = true;
 253     writeHeader(GREETER_MESSAGE_CANCEL_AUTHENTICATION, 0);
 254     flush();
 255 }
 256
 257 bool Greeter::inAuthentication() const
 258 {
 259     return d->inAuthentication;
 260 }
 261
 262 bool Greeter::isAuthenticated() const
 263 {
 264     return d->isAuthenticated;
 265 }
 266
 267 QString Greeter::authenticationUser() const
 268 {
 269     return d->authenticationUser;
 270 }
 271
 272 void Greeter::startSession(const QString &session)
 273 {
 274     qDebug() << "Starting session " << session;
 275     writeHeader(GREETER_MESSAGE_START_SESSION, stringLength(session));
 276     writeString(session);
 277     flush();
 278 }
 279
 280 void Greeter::onRead(int fd)
 281 {
 282     //qDebug() << "Reading from server";
 283
 284     int nToRead = HEADER_SIZE;
 285     if(d->nRead >= HEADER_SIZE)
 286         nToRead += getPacketLength();
 287
 288     ssize_t nRead;
 289     nRead = read(fd, d->readBuffer + d->nRead, nToRead - d->nRead);
 290     if(nRead < 0)
 291     {
 292         qDebug() << "Error reading from server";
 293         return;
 294     }
 295     if (nRead == 0)
 296     {
 297         qDebug() << "EOF reading from server";
 298         return;
 299     }
 300
 301     //qDebug() << "Read " << nRead << "octets";
 302     d->nRead += nRead;
 303     if(d->nRead != nToRead)
 304         return;
 305
 306     /* If have header, rerun for content */
 307     if(d->nRead == HEADER_SIZE)
 308     {
 309         nToRead = getPacketLength();
 310         if(nToRead > 0)
 311         {
 312             d->readBuffer = (char *)realloc(d->readBuffer, HEADER_SIZE + nToRead);
 313             onRead(fd);
 314             return;
 315         }
 316     }
 317
 318     int offset = 0;
 319     int id = readInt(&offset);
 320     int length = readInt(&offset);
 321     int nMessages, sequenceNumber, returnCode;
 322     QString version, username;
 323     QString hintString = "";
 324     switch(id)
 325     {
 326     case SERVER_MESSAGE_CONNECTED:
 327         version = readString(&offset);
 328         while (offset < length)
 329         {
 330             QString name = readString(&offset);
 331             QString value = readString(&offset);
 332             hintString.append (" ");
 333             hintString.append (name);
 334             hintString.append ("=");
 335             hintString.append (value);
 336         }
 337
 338         qDebug() << "Connected version=" << version << hintString;
 339
 340         emit connected();
 341         break;
 342     case SERVER_MESSAGE_QUIT:
 343         qDebug() << "Got quit request from server";
 344         emit quit();
 345         break;
 346     case SERVER_MESSAGE_PROMPT_AUTHENTICATION:
 347         sequenceNumber = readInt(&offset);
 348
 349         if (sequenceNumber == d->authenticateSequenceNumber &&
 350             !d->cancellingAuthentication)
 351         {
 352             nMessages = readInt(&offset);
 353             qDebug() << "Prompt user with " << nMessages << " message(s)";
 354             for(int i = 0; i < nMessages; i++)
 355             {
 356                 int msg_style = readInt (&offset);
 357                 QString msg = readString (&offset);
 358
 359                 // FIXME: Should stop on prompts?
 360                 switch (msg_style)
 361                 {
 362                 case PAM_PROMPT_ECHO_OFF:
 363                 case PAM_PROMPT_ECHO_ON:
 364                     emit showPrompt(msg);
 365                     break;
 366                 case PAM_ERROR_MSG:
 367                     emit showError(msg);
 368                     break;
 369                 case PAM_TEXT_INFO:
 370                     emit showMessage(msg);
 371                     break;
 372                 }
 373             }
 374         }
 375         break;
 376     case SERVER_MESSAGE_END_AUTHENTICATION:
 377         sequenceNumber = readInt(&offset);
 378         returnCode = readInt(&offset);
 379
 380         if (sequenceNumber == d->authenticateSequenceNumber)
 381         {
 382             qDebug() << "Authentication complete with return code " << returnCode;
 383             d->cancellingAuthentication = false;
 384             d->isAuthenticated = (returnCode == 0);
 385             if(!d->isAuthenticated) {
 386                 d->authenticationUser = "";
 387             }
 388             emit authenticationComplete(d->isAuthenticated);
 389             d->inAuthentication = false;
 390         }
 391         else
 392             qDebug () << "Ignoring end authentication with invalid sequence number " << sequenceNumber;
 393         break;
 394     case SERVER_MESSAGE_SESSION_FAILED:
 395         qDebug() << "Session failed to start";
 396         emit sessionFailed();
 397         break;
 398     default:
 399         qDebug() << "Unknown message from server: " << id;
 400     }
 401
 402     d->nRead = 0;
 403 }
 404
 405 QString Greeter::hostname() const
 406 {
 407     return QHostInfo::localHostName();
 408 }
 409
 410 QString Greeter::defaultLanguage() const
 411 {
 412     return getenv("LANG");
 413 }
 414
 415 QString Greeter::getHint(QString name) const
 416 {
 417     return d->hints.value (name);
 418 }
 419
 420 QString Greeter::defaultSessionHint() const
 421 {
 422     return getHint ("default-session");
 423 }
 424
 425 bool Greeter::hideUsersHint() const
 426 {
 427     return d->hints.value ("hide-users", "true") == "true";
 428 }
 429
 430 bool Greeter::hasGuestAccountHint() const
 431 {
 432     return d->hints.value ("has-guest-account", "false") == "true";
 433 }
 434
 435 QString Greeter::selectUserHint() const
 436 {
 437     return getHint ("select-user");
 438 }
 439
 440 bool Greeter::selectGuestHint() const
 441 {
 442     return d->hints.value ("select-guest", "false") == "true";
 443 }
 444
 445 QString Greeter::autologinUserHint() const
 446 {
 447     return getHint ("autologin-user");
 448 }
 449
 450 bool Greeter::autologinGuestHint() const
 451 {
 452     return d->hints.value ("autologin-guest", "false") == "true";
 453 }
 454
 455 int Greeter::autologinTimeoutHint() const
 456 {
 457     return d->hints.value ("autologin-timeout", "0").toInt ();
 458 }
 459
 460 bool Greeter::canSuspend() const
 461 {
 462     QDBusReply<bool> reply = d->powerManagementInterface->call("CanSuspend");
 463     if (reply.isValid())
 464         return reply.value();
 465     else
 466         return false;
 467 }
 468
 469 void Greeter::suspend()
 470 {
 471     d->powerManagementInterface->call("Suspend");
 472 }
 473
 474 bool Greeter::canHibernate() const
 475 {
 476     QDBusReply<bool> reply = d->powerManagementInterface->call("CanHibernate");
 477     if (reply.isValid())
 478         return reply.value();
 479     else
 480         return false;
 481 }
 482
 483 void Greeter::hibernate()
 484 {
 485     d->powerManagementInterface->call("Hibernate");
 486 }
 487
 488 bool Greeter::canShutdown() const
 489 {
 490     QDBusReply<bool> reply = d->consoleKitInterface->call("CanStop");
 491     if (reply.isValid())
 492         return reply.value();
 493     else
 494         return false;
 495 }
 496
 497 void Greeter::shutdown()
 498 {
 499     d->consoleKitInterface->call("stop");
 500 }
 501
 502 bool Greeter::canRestart() const
 503 {
 504     QDBusReply<bool> reply = d->consoleKitInterface->call("CanRestart");
 505     if (reply.isValid())
 506         return reply.value();
 507     else
 508         return false;
 509 }
 510
 511 void Greeter::restart()
 512 {
 513     d->consoleKitInterface->call("Restart");
 514 }