/*
 * Dibbler - a portable DHCPv6
 *
 * authors: Tomasz Mrugalski <thomson@klub.com.pl>
 *          Marek Senderski <msend@o2.pl>
 *
 * released under GNU GPL v2 only licence
 *
 */

#include "AddrIA.h"
#include "ClntCfgIA.h"
#include "ClntOptIA_NA.h"
#include "ClntOptIAAddress.h"
#include "ClntOptStatusCode.h"
#include "ClntOptAddrParams.h"
#include "Logger.h"
#include "Msg.h"
#include "ClntAddrMgr.h"
#include "ClntIfaceMgr.h"

/**
 * Used in CONFIRM constructor
 *
 * @param clntAddrIA
 * @param zeroTimes
 * @param parent
 */
TClntOptIA_NA::TClntOptIA_NA(SPtr<TAddrIA> clntAddrIA, bool zeroTimes, TMsg* parent)
    :TOptIA_NA(clntAddrIA->getIAID(), zeroTimes?0:clntAddrIA->getT1(),
               zeroTimes?0:clntAddrIA->getT2(), parent), Iface_(0)
{
    SPtr <TAddrAddr> addr;
    clntAddrIA->firstAddr();
    while ( addr = clntAddrIA->getAddr() ) {
        SubOptions.append( new TClntOptIAAddress(addr->get(),
                                                 zeroTimes?0:addr->getPref(),
                                                 zeroTimes?0:addr->getValid(),
                                                 parent) );
    }
}

/**
 * Used in DECLINE, RENEW and RELEASE
 *
 * @param addrIA
 * @param parent
 */
TClntOptIA_NA::TClntOptIA_NA(SPtr<TAddrIA> addrIA, TMsg* parent)
    :TOptIA_NA(addrIA->getIAID(),addrIA->getT1(),addrIA->getT2(), parent)
{
    // should we include all addrs or tentative ones only?
    bool decline;
    if (parent->getType()==DECLINE_MSG)
        decline = true;
    else
        decline = false;

    bool zeroTimes = false;
    if ( (parent->getType()==RELEASE_MSG) || (parent->getType()==DECLINE_MSG)) {
        T1_ = 0;
        T2_ = 0;
        zeroTimes = true;
    }

    SPtr<TAddrAddr> ptrAddr;
    addrIA->firstAddr();
    while ( ptrAddr = addrIA->getAddr() )
    {
        if ( !decline || (ptrAddr->getTentative()==ADDRSTATUS_YES) )
            SubOptions.append(new TClntOptIAAddress(ptrAddr->get(), zeroTimes?0:ptrAddr->getPref(),
                                                    zeroTimes?0:ptrAddr->getValid(),this->Parent) );
    }
    DUID = SPtr<TDUID>(); // NULL
}

/**
 * Used in REQUEST constructor
 *
 * @param ClntCfgIA
 * @param ClntaddrIA
 * @param parent
 */
TClntOptIA_NA::TClntOptIA_NA(SPtr<TClntCfgIA> ClntCfgIA, SPtr<TAddrIA> ClntaddrIA, TMsg* parent)
    :TOptIA_NA(ClntaddrIA->getIAID(),ClntaddrIA->getT1(),ClntaddrIA->getT2(), parent)
{
    //checkRequestConstructor
    ClntCfgIA->firstAddr();
    SPtr<TClntCfgAddr> ClntCfgAddr;

    /// @todo: keep allocated address in TAddrClient
    while ((ClntCfgAddr = ClntCfgIA->getAddr())&&
        ((ClntCfgIA->countAddr()-ClntaddrIA->countAddr())>this->countAddr() ))
    {
        SPtr<TAddrAddr> ptrAddr=ClntaddrIA->getAddr(ClntCfgAddr->get());
        if(!ptrAddr)
            SubOptions.append(new TClntOptIAAddress(
            ClntCfgAddr->get(),
            ClntCfgAddr->getPref(),
            ClntCfgAddr->getValid(),
            this->Parent));
    }
    DUID = SPtr<TDUID>(); // NULL
}

/**
 * Used in SOLICIT constructor
 *
 * @param ClntCfgIA
 * @param parent
 */
TClntOptIA_NA::TClntOptIA_NA(SPtr<TClntCfgIA> ClntCfgIA, TMsg* parent)
    :TOptIA_NA(ClntCfgIA->getIAID(),ClntCfgIA->getT1(),ClntCfgIA->getT2(), parent)
{
    ClntCfgIA->firstAddr();
    SPtr<TClntCfgAddr> ClntCfgAddr;
    // just copy all addresses defined in the CfgMgr
    while (ClntCfgAddr = ClntCfgIA->getAddr())
        SubOptions.append(new TClntOptIAAddress(ClntCfgAddr->get(),
        ClntCfgAddr->getPref(),
        ClntCfgAddr->getValid(),this->Parent) );
    DUID = SPtr<TDUID>(); // NULL
}

/**
 * Used to create object from received message
 *
 * @param buf
 * @param bufsize
 * @param parent
 */
TClntOptIA_NA::TClntOptIA_NA(char * buf,int bufsize, TMsg* parent)
:TOptIA_NA(buf,bufsize, parent)
{
    int pos=0;
    while(pos<bufsize)
    {
        if (pos+4>bufsize) {
            Log(Warning) << "Truncated IA_NA option received." << LogEnd;
            return;
        }
        int code=buf[pos]*256+buf[pos+1];
        pos+=2;
        int length=buf[pos]*256+buf[pos+1];
        pos+=2;
        if ((code>0)&&(code<=24))
        {
            if(allowOptInOpt(parent->getType(),OPTION_IA_NA,code))
            {
                switch (code)
                {
                case OPTION_IAADDR:
                    SubOptions.append( new TClntOptIAAddress(buf+pos,length,this->Parent));
                    break;
                case OPTION_STATUS_CODE:
                    SubOptions.append( new TClntOptStatusCode(buf+pos,length,this->Parent));
                    break;
                default:
                    Log(Warning) <<"Option opttype=" << code<< "not supported "
                        <<" in field of message (type="<< parent->getType()
                        <<") in this version of server."<<LogEnd;
                    break;
                }
            }
            else
                Log(Warning) << "Illegal option received, opttype=" << code
                << " in field options of IA_NA option"<<LogEnd;
        }
        else
        {
            Log(Warning) <<"Unknown option in option IA_NA( optType="
                         << code << "). Option ignored." << LogEnd;
        };
        pos+=length;
    }
}

void TClntOptIA_NA::firstAddr()
{
    SubOptions.first();
}

SPtr<TClntOptIAAddress> TClntOptIA_NA::getAddr()
{
    SPtr<TClntOptIAAddress> ptr;
    do {
        ptr = (Ptr*) SubOptions.get();
        if (ptr)
            if (ptr->getOptType()==OPTION_IAADDR)
                return ptr;
    } while (ptr);
    return SPtr<TClntOptIAAddress>();
}

int TClntOptIA_NA::countAddr()
{
    SPtr< TOpt> ptr;
    SubOptions.first();
    int count = 0;
    while ( ptr = SubOptions.get() ) {
        if (ptr->getOptType() == OPTION_IAADDR)
            count++;
    }
    return count;
}

int TClntOptIA_NA::getStatusCode()
{
    SPtr<TOpt> option;
    if (option=getOption(OPTION_STATUS_CODE))
    {
        SPtr<TClntOptStatusCode> statOpt=(Ptr*) option;
        return statOpt->getCode();
    }
    return STATUSCODE_SUCCESS;
}

void TClntOptIA_NA::setContext(SPtr<TDUID> srvDuid, SPtr<TIPv6Addr> srvAddr, int iface)
{
    DUID = srvDuid;
    Addr = srvAddr;
    Iface_ = iface;
}

TClntOptIA_NA::~TClntOptIA_NA() {

}

bool TClntOptIA_NA::doDuties() {

    // find this IA in addrMgr...
    SPtr<TAddrIA> ptrIA=ClntAddrMgr().getIA(this->getIAID());
    if (!ptrIA) {
        // unknown IAID, ignore it
        Log(Warning) << "Received message contains unknown IA (IAID="
                     << this->getIAID() << "). We didn't order it. Weird... ignoring it." << LogEnd;
        return true;
    }

    // IAID found, set up new received options.
    SPtr<TAddrAddr> ptrAddrAddr;
    SPtr<TClntOptIAAddress> ptrOptAddr;

    SPtr<TIfaceIface> ptrIface;
    ptrIface = ClntIfaceMgr().getIfaceByID(Iface_);
    if (!ptrIface)
    {
        Log(Error) << "Interface with ifindex=" << Iface_ << " not found." << LogEnd;
        return true;
    }

    // for each address in IA option...
    this->firstAddr();
    while (ptrOptAddr = this->getAddr() ) {
        ptrAddrAddr = ptrIA->getAddr( ptrOptAddr->getAddr() );

        // no such address in DB ??
        if (!ptrAddrAddr) {
            if (ptrOptAddr->getValid()) {

                int prefixLen = ptrIface->getPrefixLength();
                if (ptrOptAddr->getOption(OPTION_ADDRPARAMS)) {
                    Log(Debug) << "Experimental addr-params found." << LogEnd;
                    SPtr<TClntOptAddrParams> optAddrParams = (Ptr*) ptrOptAddr->getOption(OPTION_ADDRPARAMS);
                    prefixLen = optAddrParams->getPrefix();
                }

                // add this address in addrDB...
                ptrIA->addAddr(ptrOptAddr->getAddr(), ptrOptAddr->getPref(), ptrOptAddr->getValid(), prefixLen);
                ptrIA->setDUID(this->DUID);

                // ... and in IfaceMgr -
                ptrIface->addAddr(ptrOptAddr->getAddr(), ptrOptAddr->getPref(), ptrOptAddr->getValid(), prefixLen);
            }
            else {
                Log(Warning) << "Server send new addr with valid lifetime 0." << LogEnd;
            }
        } else {
            // we have this addr in DB
            if ( ptrOptAddr->getValid() == 0 ) {
                // valid=0, release this address
                // delete address from addrDB
                ptrIA->delAddr(ptrOptAddr->getAddr());
                // delete address from IfaceMgr
                ptrIface->delAddr(ptrOptAddr->getAddr(), ptrIface->getPrefixLength());
                break; // analyze next option OPTION_IA_NA
            }

            // set up new options in IfaceMgr
            SPtr<TIfaceIface> ptrIface = ClntIfaceMgr().getIfaceByID(Iface_);
            if (ptrIface)
                ptrIface->updateAddr(ptrOptAddr->getAddr(),
                        ptrOptAddr->getPref(),
                        ptrOptAddr->getValid());
            // set up new options in addrDB
            ptrAddrAddr->setPref(ptrOptAddr->getPref());
            ptrAddrAddr->setValid(ptrOptAddr->getValid());
            ptrAddrAddr->setTimestamp();
        }
    }
    SPtr<TClntCfgIA> ptrCfgIA;
    ptrCfgIA=ClntCfgMgr().getIA(ptrIA->getIAID());

    if (getT1() && getT2()) {
        ptrIA->setT1( this->getT1() );
        ptrIA->setT2( this->getT2() );
        Log(Debug) << "RENEW(IA_NA) will be sent (T1) after " << ptrIA->getT1()
                   << ", REBIND (T2) after " << ptrIA->getT2() << " seconds." << LogEnd;
    } else {
        this->firstAddr();
        ptrOptAddr = this->getAddr();
        if (ptrOptAddr) {
            ptrIA->setT1( ptrOptAddr->getPref()/2);
            ptrIA->setT2( (int)((ptrOptAddr->getPref())*0.7) );
            Log(Notice) << "Server set T1 and T2 to 0. Choosing default (50%, "
                        << "70% * prefered-lifetime): T1=" << ptrIA->getT1()
                        << ", T2=" << ptrIA->getT2() << LogEnd;
        }
    }

    ptrIA->setTimestamp();
    ptrIA->setState(STATE_CONFIGURED);
    ptrCfgIA->setState(STATE_CONFIGURED);
    return true;
}

//Counts all valid and diffrent addresses in sum of
//addresses received in IA from server and addresses contained
//in its counterpart IA in address manager
int TClntOptIA_NA::countValidAddrs(SPtr<TAddrIA> ptrIA)
{
    int count=0;

    //Counts addresses not received in Reply message
    //but which are in addrDB, and are still valid (valid>0)
    SPtr<TAddrAddr> ptrAddr;
    ptrIA->firstAddr();
    //For each addr in DB for this IA
    while(ptrAddr = ptrIA->getAddr())
    {
        //If addr is still valid
        if (!ptrAddr->getValid())
            continue;
        //and is not included in received option
        if (!this->getAddr(ptrAddr->get()))
            //we can increase counter
            count++;
    }

    //count all valid (valid>0) addresses received from server
    /// @todo: A) check if they repeats (possible with maliciious server)
    //       B) and not already assigned in addrDB (in others IAs)
    //       It's easy and worth checking
    //       A) Create list of valid addrs and add new valid addr
    //          only if it doesn't exist already on this list
    //       B) Address can be assigned only in this IA, not in other
    //          This could be ommited if VerifyIA worked prooperly
    this->firstAddr();
    SPtr<TClntOptIAAddress> ptrOptIAAddr;
    while(ptrOptIAAddr=this->getAddr())
    {
        if (!ptrOptIAAddr->getValid())
            continue;
        //if (!ptrIA->getAddr(ptrOptIAAddr->getAddr()))
               count++;
    }
    return count;
}

SPtr<TClntOptIAAddress> TClntOptIA_NA::getAddr(SPtr<TIPv6Addr> addr)
{
    SPtr<TClntOptIAAddress> optAddr;
    this->firstAddr();
    while(optAddr=this->getAddr())
    {
        //!memcmp(optAddr->getAddr(),addr,16)
        if ((*addr)==(*optAddr->getAddr()))
            return optAddr;
    };
    return SPtr<TClntOptIAAddress>();
}

void TClntOptIA_NA::releaseAddr(long IAID, SPtr<TIPv6Addr> addr )
{
    SPtr<TAddrIA> ptrIA = ClntAddrMgr().getIA(IAID);
    if (ptrIA)
        ptrIA->delAddr(addr);
    else
        Log(Warning) << "Unable to release addr: IA ("
                     << IAID << ") not present in addrDB." << LogEnd;
}

void TClntOptIA_NA::setIface(int iface) {
    Iface_ = iface;
}

bool TClntOptIA_NA::isValid() const {

    const TOptList& opts = SubOptions.getSTL();

    for (TOptList::const_iterator it = opts.begin(); it != opts.end(); ++it) {
        if ((*it)->getOptType() != OPTION_IAADDR)
            continue;
        const TOptIAAddress* addr = (const TOptIAAddress*)it->get();

        if (addr->getAddr()->linkLocal()) {
            Log(Warning) << "Address " << addr->getAddr()->getPlain() << " used in IA_NA (IAID="
                         << IAID_ << ") is link local. The whole IA option is considered invalid."
                         << LogEnd;
            return false;
        }
    }

    // RFC3315, section 22.4:
    // If a client receives an IA_NA with T1 greater than T2, and both T1
    // and T2 are greater than 0, the client discards the IA_NA option and
    // processes the remainder of the message as though the server had not
    // included the invalid IA_NA option.
    if (T1_ > T2_) {
        Log(Warning) << "Received malformed IA_NA: T1(" << T1_ << ") is greater than T2("
                     << T2_ << "). Ignoring IA_NA." << LogEnd;
        return false;
    }

    return Valid;
}