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#ifndef SSHINCOMINGPACKET_P_H
#define SSHINCOMINGPACKET_P_H

#include "sshpacket_p.h"

#include "sshcryptofacility_p.h"
#include "sshpacketparser_p.h"

#include <QStringList>

namespace QSsh {
namespace Internal {

class SshKeyExchange;

struct SshKeyExchangeInit
{
    char cookie[16];
    SshNameList keyAlgorithms;
    SshNameList serverHostKeyAlgorithms;
    SshNameList encryptionAlgorithmsClientToServer;
    SshNameList encryptionAlgorithmsServerToClient;
    SshNameList macAlgorithmsClientToServer;
    SshNameList macAlgorithmsServerToClient;
    SshNameList compressionAlgorithmsClientToServer;
    SshNameList compressionAlgorithmsServerToClient;
    SshNameList languagesClientToServer;
    SshNameList languagesServerToClient;
    bool firstKexPacketFollows;
};

struct SshKeyExchangeReply
{
    QByteArray k_s;
    QList<Botan::BigInt> parameters; // DSS: p, q, g, y. RSA: e, n.
    Botan::BigInt f;
    QByteArray signatureBlob;
};

struct SshDisconnect
{
    quint32 reasonCode;
    QString description;
    QByteArray language;
};

struct SshUserAuthBanner
{
    QString message;
    QByteArray language;
};

struct SshUserAuthInfoRequestPacket
{
    QString name;
    QString instruction;
    QByteArray languageTag;
    QStringList prompts;
    QList<bool> echos;
};

struct SshDebug
{
    bool display;
    QString message;
    QByteArray language;
};

struct SshUnimplemented
{
    quint32 invalidMsgSeqNr;
};

struct SshChannelOpenFailure
{
    quint32 localChannel;
    quint32 reasonCode;
    QString reasonString;
    QByteArray language;
};

struct SshChannelOpenConfirmation
{
    quint32 localChannel;
    quint32 remoteChannel;
    quint32 remoteWindowSize;
    quint32 remoteMaxPacketSize;
};

struct SshChannelWindowAdjust
{
    quint32 localChannel;
    quint32 bytesToAdd;
};

struct SshChannelData
{
    quint32 localChannel;
    QByteArray data;
};

struct SshChannelExtendedData
{
    quint32 localChannel;
    quint32 type;
    QByteArray data;
};

struct SshChannelExitStatus
{
    quint32 localChannel;
    quint32 exitStatus;
};

struct SshChannelExitSignal
{
    quint32 localChannel;
    QByteArray signal;
    bool coreDumped;
    QString error;
    QByteArray language;
};


class SshIncomingPacket : public AbstractSshPacket
{
public:
    SshIncomingPacket();

    void consumeData(QByteArray &data);
    void recreateKeys(const SshKeyExchange &keyExchange);
    void reset();

    SshKeyExchangeInit extractKeyExchangeInitData() const;
    SshKeyExchangeReply extractKeyExchangeReply(const QByteArray &pubKeyAlgo) const;
    SshDisconnect extractDisconnect() const;
    SshUserAuthBanner extractUserAuthBanner() const;
    SshUserAuthInfoRequestPacket extractUserAuthInfoRequest() const;
    SshDebug extractDebug() const;
    SshUnimplemented extractUnimplemented() const;

    SshChannelOpenFailure extractChannelOpenFailure() const;
    SshChannelOpenConfirmation extractChannelOpenConfirmation() const;
    SshChannelWindowAdjust extractWindowAdjust() const;
    SshChannelData extractChannelData() const;
    SshChannelExtendedData extractChannelExtendedData() const;
    SshChannelExitStatus extractChannelExitStatus() const;
    SshChannelExitSignal extractChannelExitSignal() const;
    quint32 extractRecipientChannel() const;
    QByteArray extractChannelRequestType() const;

    quint32 serverSeqNr() const { return m_serverSeqNr; }

    static const QByteArray ExitStatusType;
    static const QByteArray ExitSignalType;

private:
    virtual quint32 cipherBlockSize() const;
    virtual quint32 macLength() const;
    virtual void calculateLength() const;

    void decrypt();
    void moveFirstBytes(QByteArray &target, QByteArray &source, int n);

    quint32 m_serverSeqNr;
    SshDecryptionFacility m_decrypter;
};

} // namespace Internal
} // namespace QSsh

#endif // SSHINCOMINGPACKET_P_H
