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** Copyright (C) 2016 Intel Corporation.
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** Alternatively, this file may be used under the terms of the GNU
** General Public License version 2.0 or (at your option) the GNU General
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****************************************************************************/

#include "qnetworkinterface.h"
#include "qnetworkinterface_p.h"

#include "qdebug.h"
#include "qendian.h"
#include "private/qtools_p.h"

#ifndef QT_NO_NETWORKINTERFACE

QT_BEGIN_NAMESPACE

static QList<QNetworkInterfacePrivate *> postProcess(QList<QNetworkInterfacePrivate *> list)
{
    // Some platforms report a netmask but don't report a broadcast address
    // Go through all available addresses and calculate the broadcast address
    // from the IP and the netmask
    //
    // This is an IPv4-only thing -- IPv6 has no concept of broadcasts
    // The math is:
    //    broadcast = IP | ~netmask

    QList<QNetworkInterfacePrivate *>::Iterator it = list.begin();
    const QList<QNetworkInterfacePrivate *>::Iterator end = list.end();
    for ( ; it != end; ++it) {
        QList<QNetworkAddressEntry>::Iterator addr_it = (*it)->addressEntries.begin();
        const QList<QNetworkAddressEntry>::Iterator addr_end = (*it)->addressEntries.end();
        for ( ; addr_it != addr_end; ++addr_it) {
            if (addr_it->ip().protocol() != QAbstractSocket::IPv4Protocol)
                continue;

            if (!addr_it->netmask().isNull() && addr_it->broadcast().isNull()) {
                QHostAddress bcast = addr_it->ip();
                bcast = QHostAddress(bcast.toIPv4Address() | ~addr_it->netmask().toIPv4Address());
                addr_it->setBroadcast(bcast);
            }
        }
    }

    return list;
}

Q_GLOBAL_STATIC(QNetworkInterfaceManager, manager)

QNetworkInterfaceManager::QNetworkInterfaceManager()
{
}

QNetworkInterfaceManager::~QNetworkInterfaceManager()
{
}

QSharedDataPointer<QNetworkInterfacePrivate> QNetworkInterfaceManager::interfaceFromName(const QString &name)
{
    QList<QSharedDataPointer<QNetworkInterfacePrivate> > interfaceList = allInterfaces();
    QList<QSharedDataPointer<QNetworkInterfacePrivate> >::ConstIterator it = interfaceList.constBegin();

    bool ok;
    uint index = name.toUInt(&ok);

    for ( ; it != interfaceList.constEnd(); ++it) {
        if (ok && (*it)->index == int(index))
            return *it;
        else if ((*it)->name == name)
            return *it;
    }

    return empty;
}

QSharedDataPointer<QNetworkInterfacePrivate> QNetworkInterfaceManager::interfaceFromIndex(int index)
{
    QList<QSharedDataPointer<QNetworkInterfacePrivate> > interfaceList = allInterfaces();
    QList<QSharedDataPointer<QNetworkInterfacePrivate> >::ConstIterator it = interfaceList.constBegin();
    for ( ; it != interfaceList.constEnd(); ++it)
        if ((*it)->index == index)
            return *it;

    return empty;
}

QList<QSharedDataPointer<QNetworkInterfacePrivate> > QNetworkInterfaceManager::allInterfaces()
{
    const QList<QNetworkInterfacePrivate *> list = postProcess(scan());
    QList<QSharedDataPointer<QNetworkInterfacePrivate> > result;
    result.reserve(list.size());

    for (QNetworkInterfacePrivate *ptr : list)
        result << QSharedDataPointer<QNetworkInterfacePrivate>(ptr);

    return result;
}

QString QNetworkInterfacePrivate::makeHwAddress(int len, uchar *data)
{
    const int outLen = qMax(len * 2 + (len - 1) * 1, 0);
    QString result(outLen, Qt::Uninitialized);
    QChar *out = result.data();
    for (int i = 0; i < len; ++i) {
        if (i)
            *out++ = QLatin1Char(':');
        *out++ = QLatin1Char(QtMiscUtils::toHexUpper(data[i] / 16));
        *out++ = QLatin1Char(QtMiscUtils::toHexUpper(data[i] % 16));
    }
    return result;
}

/*!
    \class QNetworkAddressEntry
    \brief The QNetworkAddressEntry class stores one IP address
    supported by a network interface, along with its associated
    netmask and broadcast address.

    \since 4.2
    \reentrant
    \ingroup network
    \ingroup shared
    \inmodule QtNetwork

    Each network interface can contain zero or more IP addresses, which
    in turn can be associated with a netmask and/or a broadcast
    address (depending on support from the operating system).

    This class represents one such group.
*/

/*!
    Constructs an empty QNetworkAddressEntry object.
*/
QNetworkAddressEntry::QNetworkAddressEntry()
    : d(new QNetworkAddressEntryPrivate)
{
}

/*!
    Constructs a QNetworkAddressEntry object that is a copy of the
    object \a other.
*/
QNetworkAddressEntry::QNetworkAddressEntry(const QNetworkAddressEntry &other)
    : d(new QNetworkAddressEntryPrivate(*other.d.data()))
{
}

/*!
    Makes a copy of the QNetworkAddressEntry object \a other.
*/
QNetworkAddressEntry &QNetworkAddressEntry::operator=(const QNetworkAddressEntry &other)
{
    *d.data() = *other.d.data();
    return *this;
}

/*!
    \fn void QNetworkAddressEntry::swap(QNetworkAddressEntry &other)
    \since 5.0

    Swaps this network address entry instance with \a other. This
    function is very fast and never fails.
*/

/*!
    Destroys this QNetworkAddressEntry object.
*/
QNetworkAddressEntry::~QNetworkAddressEntry()
{
}

/*!
    Returns \c true if this network address entry is the same as \a
    other.
*/
bool QNetworkAddressEntry::operator==(const QNetworkAddressEntry &other) const
{
    if (d == other.d) return true;
    if (!d || !other.d) return false;
    return d->address == other.d->address &&
        d->netmask == other.d->netmask &&
        d->broadcast == other.d->broadcast;
}

/*!
    \fn bool QNetworkAddressEntry::operator!=(const QNetworkAddressEntry &other) const

    Returns \c true if this network address entry is different from \a
    other.
*/

/*!
    This function returns one IPv4 or IPv6 address found, that was
    found in a network interface.
*/
QHostAddress QNetworkAddressEntry::ip() const
{
    return d->address;
}

/*!
    Sets the IP address the QNetworkAddressEntry object contains to \a
    newIp.
*/
void QNetworkAddressEntry::setIp(const QHostAddress &newIp)
{
    d->address = newIp;
}

/*!
    Returns the netmask associated with the IP address. The
    netmask is expressed in the form of an IP address, such as
    255.255.0.0.

    For IPv6 addresses, the prefix length is converted to an address
    where the number of bits set to 1 is equal to the prefix
    length. For a prefix length of 64 bits (the most common value),
    the netmask will be expressed as a QHostAddress holding the
    address FFFF:FFFF:FFFF:FFFF::

    \sa prefixLength()
*/
QHostAddress QNetworkAddressEntry::netmask() const
{
    return d->netmask;
}

/*!
    Sets the netmask that this QNetworkAddressEntry object contains to
    \a newNetmask. Setting the netmask also sets the prefix length to
    match the new netmask.

    \sa setPrefixLength()
*/
void QNetworkAddressEntry::setNetmask(const QHostAddress &newNetmask)
{
    if (newNetmask.protocol() != ip().protocol()) {
        d->netmask = QNetmaskAddress();
        return;
    }

    d->netmask.setAddress(newNetmask);
}

/*!
    \since 4.5
    Returns the prefix length of this IP address. The prefix length
    matches the number of bits set to 1 in the netmask (see
    netmask()). For IPv4 addresses, the value is between 0 and 32. For
    IPv6 addresses, it's contained between 0 and 128 and is the
    preferred form of representing addresses.

    This function returns -1 if the prefix length could not be
    determined (i.e., netmask() returns a null QHostAddress()).

    \sa netmask()
*/
int QNetworkAddressEntry::prefixLength() const
{
    return d->netmask.prefixLength();
}

/*!
    \since 4.5
    Sets the prefix length of this IP address to \a length. The value
    of \a length must be valid for this type of IP address: between 0
    and 32 for IPv4 addresses, between 0 and 128 for IPv6
    addresses. Setting to any invalid value is equivalent to setting
    to -1, which means "no prefix length".

    Setting the prefix length also sets the netmask (see netmask()).

    \sa setNetmask()
*/
void QNetworkAddressEntry::setPrefixLength(int length)
{
    d->netmask.setPrefixLength(d->address.protocol(), length);
}

/*!
    Returns the broadcast address associated with the IPv4
    address and netmask. It can usually be derived from those two by
    setting to 1 the bits of the IP address where the netmask contains
    a 0. (In other words, by bitwise-OR'ing the IP address with the
    inverse of the netmask)

    This member is always empty for IPv6 addresses, since the concept
    of broadcast has been abandoned in that system in favor of
    multicast. In particular, the group of hosts corresponding to all
    the nodes in the local network can be reached by the "all-nodes"
    special multicast group (address FF02::1).
*/
QHostAddress QNetworkAddressEntry::broadcast() const
{
    return d->broadcast;
}

/*!
    Sets the broadcast IP address of this QNetworkAddressEntry object
    to \a newBroadcast.
*/
void QNetworkAddressEntry::setBroadcast(const QHostAddress &newBroadcast)
{
    d->broadcast = newBroadcast;
}

/*!
    \class QNetworkInterface
    \brief The QNetworkInterface class provides a listing of the host's IP
    addresses and network interfaces.

    \since 4.2
    \reentrant
    \ingroup network
    \ingroup shared
    \inmodule QtNetwork

    QNetworkInterface represents one network interface attached to the
    host where the program is being run. Each network interface may
    contain zero or more IP addresses, each of which is optionally
    associated with a netmask and/or a broadcast address. The list of
    such trios can be obtained with addressEntries(). Alternatively,
    when the netmask or the broadcast addresses aren't necessary, use
    the allAddresses() convenience function to obtain just the IP
    addresses.

    QNetworkInterface also reports the interface's hardware address with
    hardwareAddress().

    Not all operating systems support reporting all features. Only the
    IPv4 addresses are guaranteed to be listed by this class in all
    platforms. In particular, IPv6 address listing is only supported
    on Windows, Linux, OS X and the BSDs.

    \sa QNetworkAddressEntry
*/

/*!
    \enum QNetworkInterface::InterfaceFlag
    Specifies the flags associated with this network interface. The
    possible values are:

    \value IsUp                 the network interface is active
    \value IsRunning            the network interface has resources
                                allocated
    \value CanBroadcast         the network interface works in
                                broadcast mode
    \value IsLoopBack           the network interface is a loopback
                                interface: that is, it's a virtual
                                interface whose destination is the
                                host computer itself
    \value IsPointToPoint       the network interface is a
                                point-to-point interface: that is,
                                there is one, single other address
                                that can be directly reached by it.
    \value CanMulticast         the network interface supports
                                multicasting

    Note that one network interface cannot be both broadcast-based and
    point-to-point.
*/

/*!
    Constructs an empty network interface object.
*/
QNetworkInterface::QNetworkInterface()
    : d(0)
{
}

/*!
    Frees the resources associated with the QNetworkInterface object.
*/
QNetworkInterface::~QNetworkInterface()
{
}

/*!
    Creates a copy of the QNetworkInterface object contained in \a
    other.
*/
QNetworkInterface::QNetworkInterface(const QNetworkInterface &other)
    : d(other.d)
{
}

/*!
    Copies the contents of the QNetworkInterface object contained in \a
    other into this one.
*/
QNetworkInterface &QNetworkInterface::operator=(const QNetworkInterface &other)
{
    d = other.d;
    return *this;
}

/*!
    \fn void QNetworkInterface::swap(QNetworkInterface &other)
    \since 5.0

    Swaps this network interface instance with \a other. This function
    is very fast and never fails.
*/

/*!
    Returns \c true if this QNetworkInterface object contains valid
    information about a network interface.
*/
bool QNetworkInterface::isValid() const
{
    return !name().isEmpty();
}

/*!
    \since 4.5
    Returns the interface system index, if known. This is an integer
    assigned by the operating system to identify this interface and it
    generally doesn't change. It matches the scope ID field in IPv6
    addresses.

    If the index isn't known, this function returns 0.
*/
int QNetworkInterface::index() const
{
    return d ? d->index : 0;
}

/*!
    Returns the name of this network interface. On Unix systems, this
    is a string containing the type of the interface and optionally a
    sequence number, such as "eth0", "lo" or "pcn0". On Windows, it's
    an internal ID that cannot be changed by the user.
*/
QString QNetworkInterface::name() const
{
    return d ? d->name : QString();
}

/*!
    \since 4.5

    Returns the human-readable name of this network interface on
    Windows, such as "Local Area Connection", if the name could be
    determined. If it couldn't, this function returns the same as
    name(). The human-readable name is a name that the user can modify
    in the Windows Control Panel, so it may change during the
    execution of the program.

    On Unix, this function currently always returns the same as
    name(), since Unix systems don't store a configuration for
    human-readable names.
*/
QString QNetworkInterface::humanReadableName() const
{
    return d ? !d->friendlyName.isEmpty() ? d->friendlyName : name() : QString();
}

/*!
    Returns the flags associated with this network interface.
*/
QNetworkInterface::InterfaceFlags QNetworkInterface::flags() const
{
    return d ? d->flags : InterfaceFlags(0);
}

/*!
    Returns the low-level hardware address for this interface. On
    Ethernet interfaces, this will be a MAC address in string
    representation, separated by colons.

    Other interface types may have other types of hardware
    addresses. Implementations should not depend on this function
    returning a valid MAC address.
*/
QString QNetworkInterface::hardwareAddress() const
{
    return d ? d->hardwareAddress : QString();
}

/*!
    Returns the list of IP addresses that this interface possesses
    along with their associated netmasks and broadcast addresses.

    If the netmask or broadcast address information is not necessary,
    you can call the allAddresses() function to obtain just the IP
    addresses.
*/
QList<QNetworkAddressEntry> QNetworkInterface::addressEntries() const
{
    return d ? d->addressEntries : QList<QNetworkAddressEntry>();
}

/*!
    \since 5.7

    Returns the index of the interface whose name is \a name or 0 if there is
    no interface with that name. This function should produce the same result
    as the following code, but will probably execute faster.

    \code
        QNetworkInterface::interfaceFromName(name).index()
    \endcode

    \sa interfaceFromName(), interfaceNameFromIndex()
*/
int QNetworkInterface::interfaceIndexFromName(const QString &name)
{
    if (name.isEmpty())
        return 0;

    bool ok;
    uint id = name.toUInt(&ok);
    if (!ok)
        id = QNetworkInterfaceManager::interfaceIndexFromName(name);
    return int(id);
}

/*!
    Returns a QNetworkInterface object for the interface named \a
    name. If no such interface exists, this function returns an
    invalid QNetworkInterface object.

    The string \a name may be either an actual interface name (such as "eth0"
    or "en1") or an interface index in string form ("1", "2", etc.).

    \sa name(), isValid()
*/
QNetworkInterface QNetworkInterface::interfaceFromName(const QString &name)
{
    QNetworkInterface result;
    result.d = manager()->interfaceFromName(name);
    return result;
}

/*!
    Returns a QNetworkInterface object for the interface whose internal
    ID is \a index. Network interfaces have a unique identifier called
    the "interface index" to distinguish it from other interfaces on
    the system. Often, this value is assigned progressively and
    interfaces being removed and then added again get a different
    value every time.

    This index is also found in the IPv6 address' scope ID field.
*/
QNetworkInterface QNetworkInterface::interfaceFromIndex(int index)
{
    QNetworkInterface result;
    result.d = manager()->interfaceFromIndex(index);
    return result;
}

/*!
    \since 5.7

    Returns the name of the interface whose index is \a index or an empty
    string if there is no interface with that index. This function should
    produce the same result as the following code, but will probably execute
    faster.

    \code
        QNetworkInterface::interfaceFromIndex(index).name()
    \endcode

    \sa interfaceFromIndex(), interfaceIndexFromName()
*/
QString QNetworkInterface::interfaceNameFromIndex(int index)
{
    if (!index)
        return QString();
    return QNetworkInterfaceManager::interfaceNameFromIndex(index);
}

/*!
    Returns a listing of all the network interfaces found on the host
    machine.  In case of failure it returns a list with zero elements.
*/
QList<QNetworkInterface> QNetworkInterface::allInterfaces()
{
    const QList<QSharedDataPointer<QNetworkInterfacePrivate> > privs = manager()->allInterfaces();
    QList<QNetworkInterface> result;
    result.reserve(privs.size());
    for (const auto &p : privs) {
        QNetworkInterface item;
        item.d = p;
        result << item;
    }

    return result;
}

/*!
    This convenience function returns all IP addresses found on the
    host machine. It is equivalent to calling addressEntries() on all the
    objects returned by allInterfaces() to obtain lists of QHostAddress
    objects then calling QHostAddress::ip() on each of these.
*/
QList<QHostAddress> QNetworkInterface::allAddresses()
{
    const QList<QSharedDataPointer<QNetworkInterfacePrivate> > privs = manager()->allInterfaces();
    QList<QHostAddress> result;
    for (const auto &p : privs) {
        for (const QNetworkAddressEntry &entry : qAsConst(p->addressEntries))
            result += entry.ip();
    }

    return result;
}

#ifndef QT_NO_DEBUG_STREAM
static inline QDebug flagsDebug(QDebug debug, QNetworkInterface::InterfaceFlags flags)
{
    if (flags & QNetworkInterface::IsUp)
        debug << "IsUp ";
    if (flags & QNetworkInterface::IsRunning)
        debug << "IsRunning ";
    if (flags & QNetworkInterface::CanBroadcast)
        debug << "CanBroadcast ";
    if (flags & QNetworkInterface::IsLoopBack)
        debug << "IsLoopBack ";
    if (flags & QNetworkInterface::IsPointToPoint)
        debug << "IsPointToPoint ";
    if (flags & QNetworkInterface::CanMulticast)
        debug << "CanMulticast ";
    return debug;
}

static inline QDebug operator<<(QDebug debug, const QNetworkAddressEntry &entry)
{
    debug << "(address = " << entry.ip();
    if (!entry.netmask().isNull())
        debug << ", netmask = " << entry.netmask();
    if (!entry.broadcast().isNull())
        debug << ", broadcast = " << entry.broadcast();
    debug << ')';
    return debug;
}

QDebug operator<<(QDebug debug, const QNetworkInterface &networkInterface)
{
    QDebugStateSaver saver(debug);
    debug.resetFormat().nospace();
    debug << "QNetworkInterface(name = " << networkInterface.name()
          << ", hardware address = " << networkInterface.hardwareAddress()
          << ", flags = ";
    flagsDebug(debug, networkInterface.flags());
    debug << ", entries = " << networkInterface.addressEntries()
          << ")\n";
    return debug;
}
#endif

QT_END_NAMESPACE

#endif // QT_NO_NETWORKINTERFACE
