hush3/src/cc/heir.cpp

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#include "CCHeir.h"

/*
 The idea of Heir CC is to allow crypto inheritance.
 A special 1of2 CC address is created that is freely spendable by the creator. The heir is only allowed to spend after the specified amount of idle blocks. The idea is that if the address doesnt spend any funds for a year (or whatever amount set), then it is time to allow the heir to spend. The design requires the heir to spend all the funds at once
*/

// start of consensus code

int64_t IsHeirvout(struct CCcontract_info *cp,const CTransaction& tx,int32_t v)
{
    char destaddr[64];
    if ( tx.vout[v].scriptPubKey.IsPayToCryptoCondition() != 0 )
    {
        if ( Getscriptaddress(destaddr,tx.vout[v].scriptPubKey) > 0 && strcmp(destaddr,cp->unspendableCCaddr) == 0 )
            return(tx.vout[v].nValue);
    }
    return(0);
}

bool HeirExactAmounts(struct CCcontract_info *cp,Eval* eval,const CTransaction &tx,int32_t minage,uint64_t txfee)
{
    static uint256 zerohash;
    CTransaction vinTx; uint256 hashBlock,activehash; int32_t i,numvins,numvouts; int64_t inputs=0,outputs=0,assetoshis;
    numvins = tx.vin.size();
    numvouts = tx.vout.size();
    for (i=0; i<numvins; i++)
    {
        //fprintf(stderr,"vini.%d\n",i);
        if ( (*cp->ismyvin)(tx.vin[i].scriptSig) != 0 )
        {
            //fprintf(stderr,"vini.%d check mempool\n",i);
            if ( eval->GetTxUnconfirmed(tx.vin[i].prevout.hash,vinTx,hashBlock) == 0 )
                return eval->Invalid("cant find vinTx");
            else
            {
                //fprintf(stderr,"vini.%d check hash and vout\n",i);
                if ( hashBlock == zerohash )
                    return eval->Invalid("cant Heir from mempool");
                if ( (assetoshis= IsHeirvout(cp,vinTx,tx.vin[i].prevout.n)) != 0 )
                    inputs += assetoshis;
            }
        }
    }
    for (i=0; i<numvouts; i++)
    {
        //fprintf(stderr,"i.%d of numvouts.%d\n",i,numvouts);
        if ( (assetoshis= IsHeirvout(cp,tx,i)) != 0 )
            outputs += assetoshis;
    }
    if ( inputs != outputs+txfee )
    {
        fprintf(stderr,"inputs %llu vs outputs %llu\n",(long long)inputs,(long long)outputs);
        return eval->Invalid("mismatched inputs != outputs + txfee");
    }
    else return(true);
}

bool HeirValidate(struct CCcontract_info *cp,Eval* eval,const CTransaction &tx, uint32_t nIn)
{
    int32_t numvins,numvouts,preventCCvins,preventCCvouts,i,numblocks; bool retval; uint256 txid; uint8_t hash[32]; char str[65],destaddr[64];
    return(false);
    std::vector<std::pair<CAddressIndexKey, CAmount> > txids;
    numvins = tx.vin.size();
    numvouts = tx.vout.size();
    preventCCvins = preventCCvouts = -1;
    if ( numvouts < 1 )
        return eval->Invalid("no vouts");
    else
    {
        for (i=0; i<numvins; i++)
        {
            if ( IsCCInput(tx.vin[0].scriptSig) == 0 )
            {
                return eval->Invalid("illegal normal vini");
            }
        }
        //fprintf(stderr,"check amounts\n");
        if ( HeirExactAmounts(cp,eval,tx,1,10000) == false )
        {
            fprintf(stderr,"Heirget invalid amount\n");
            return false;
        }
        else
        {
            txid = tx.GetHash();
            memcpy(hash,&txid,sizeof(hash));
            retval = PreventCC(eval,tx,preventCCvins,numvins,preventCCvouts,numvouts);
            if ( retval != 0 )
                fprintf(stderr,"Heirget validated\n");
            else fprintf(stderr,"Heirget invalid\n");
            return(retval);
        }
    }
}
// end of consensus code

// helper functions for rpc calls in rpcwallet.cpp

int64_t AddHeirInputs(struct CCcontract_info *cp,CMutableTransaction &mtx,CPubKey pk,int64_t total,int32_t maxinputs)
{
    // add threshold check
    char coinaddr[64]; int64_t nValue,price,totalinputs = 0; uint256 txid,hashBlock; std::vector<uint8_t> origpubkey; CTransaction vintx; int32_t vout,n = 0;
    std::vector<std::pair<CAddressUnspentKey, CAddressUnspentValue> > unspentOutputs;
    GetCCaddress(cp,coinaddr,pk);
    SetCCunspents(unspentOutputs,coinaddr);
    for (std::vector<std::pair<CAddressUnspentKey, CAddressUnspentValue> >::const_iterator it=unspentOutputs.begin(); it!=unspentOutputs.end(); it++)
    {
        txid = it->first.txhash;
        vout = (int32_t)it->first.index;
        // no need to prevent dup
        if ( GetTransaction(txid,vintx,hashBlock,false) != 0 )
        {
            if ( (nValue= IsHeirvout(cp,vintx,vout)) > 1000000 && myIsutxo_spentinmempool(txid,vout) == 0 )
            {
                if ( total != 0 && maxinputs != 0 )
                    mtx.vin.push_back(CTxIn(txid,vout,CScript()));
                nValue = it->second.satoshis;
                totalinputs += nValue;
                n++;
                if ( (total > 0 && totalinputs >= total) || (maxinputs > 0 && n >= maxinputs) )
                    break;
            }
        }
    }
    return(totalinputs);
}

std::string HeirGet(uint64_t txfee,int64_t nValue)
{
    CMutableTransaction tmpmtx,mtx = CreateNewContextualCMutableTransaction(Params().GetConsensus(), komodo_nextheight());
    CPubKey mypk,Heirpk; int64_t inputs,CCchange=0; struct CCcontract_info *cp,C; std::string rawhex; uint32_t j; int32_t i,len; uint8_t buf[32768]; bits256 hash;
    cp = CCinit(&C,EVAL_HEIR);
    if ( txfee == 0 )
        txfee = 10000;
    Heirpk = GetUnspendable(cp,0);
    mypk = pubkey2pk(Mypubkey());
    if ( (inputs= AddHeirInputs(cp,mtx,Heirpk,nValue+txfee,60)) > 0 )
    {
        if ( inputs > nValue )
            CCchange = (inputs - nValue - txfee);
        if ( CCchange != 0 )
            mtx.vout.push_back(MakeCC1vout(EVAL_HEIR,CCchange,Heirpk));
        mtx.vout.push_back(CTxOut(nValue,CScript() << ParseHex(HexStr(mypk)) << OP_CHECKSIG));
        fprintf(stderr,"start at %u\n",(uint32_t)time(NULL));
        j = rand() & 0xfffffff;
        for (i=0; i<1000000; i++,j++)
        {
            tmpmtx = mtx;
            rawhex = FinalizeCCTx(-1LL,cp,tmpmtx,mypk,txfee,CScript() << OP_RETURN << E_MARSHAL(ss << (uint8_t)EVAL_HEIR << (uint8_t)'G' << j));
            if ( (len= (int32_t)rawhex.size()) > 0 && len < 65536 )
            {
                len >>= 1;
                decode_hex(buf,len,(char *)rawhex.c_str());
                hash = bits256_doublesha256(0,buf,len);
                if ( (hash.bytes[0] & 0xff) == 0 && (hash.bytes[31] & 0xff) == 0 )
                {
                    fprintf(stderr,"found valid txid after %d iterations %u\n",i,(uint32_t)time(NULL));
                    return(rawhex);
                }
                //fprintf(stderr,"%02x%02x ",hash.bytes[0],hash.bytes[31]);
            }
        }
        fprintf(stderr,"couldnt generate valid txid %u\n",(uint32_t)time(NULL));
        return("");
    } else fprintf(stderr,"cant find Heir inputs\n");
    return("");
}

std::string HeirFund(uint64_t txfee,int64_t funds)
{
    CMutableTransaction mtx = CreateNewContextualCMutableTransaction(Params().GetConsensus(), komodo_nextheight());
    CPubKey mypk,Heirpk; CScript opret; struct CCcontract_info *cp,C;
    cp = CCinit(&C,EVAL_HEIR);
    if ( txfee == 0 )
        txfee = 10000;
    mypk = pubkey2pk(Mypubkey());
    Heirpk = GetUnspendable(cp,0);
    if ( AddNormalinputs(mtx,mypk,funds+txfee,64) > 0 )
    {
        mtx.vout.push_back(MakeCC1vout(EVAL_HEIR,funds,Heirpk));
        return(FinalizeCCTx(0,cp,mtx,mypk,txfee,opret));
    }
    return("");
}

UniValue HeirInfo()
{
    CMutableTransaction mtx = CreateNewContextualCMutableTransaction(Params().GetConsensus(), komodo_nextheight());
    UniValue result(UniValue::VOBJ); char numstr[64];
    CPubKey Heirpk; struct CCcontract_info *cp,C; int64_t funding;
    result.push_back(Pair("result","success"));
    result.push_back(Pair("name","Heir"));
    cp = CCinit(&C,EVAL_HEIR);
    Heirpk = GetUnspendable(cp,0);
    funding = AddHeirInputs(cp,mtx,Heirpk,0,0);
    sprintf(numstr,"%.8f",(double)funding/COIN);
    result.push_back(Pair("funding",numstr));
    return(result);
}