From 612f676a5e035d3d8adbce3555b60649c4067c87 Mon Sep 17 00:00:00 2001 From: jl777 Date: Tue, 11 Sep 2018 03:29:47 -1100 Subject: [PATCH] CCtxidaddr enforcement --- src/cc/CCinclude.h | 1 + src/cc/CCutils.cpp | 10 ++++++++ src/cc/gateways.cpp | 62 +++++++++++++++++++++++++++++++++++++-------- src/cc/oracles.cpp | 36 ++++++++------------------ 4 files changed, 73 insertions(+), 36 deletions(-) diff --git a/src/cc/CCinclude.h b/src/cc/CCinclude.h index ba57f2748..afc113083 100644 --- a/src/cc/CCinclude.h +++ b/src/cc/CCinclude.h @@ -101,6 +101,7 @@ int32_t iguana_rwnum(int32_t rwflag,uint8_t *serialized,int32_t len,void *endian int32_t iguana_rwbignum(int32_t rwflag,uint8_t *serialized,int32_t len,uint8_t *endianedp); CScript GetScriptForMultisig(int nRequired, const std::vector& keys); int64_t CCaddress_balance(char *coinaddr); +CPubKey CCtxidaddr(char *txidaddr,uint256 txid); int64_t OraclePrice(int32_t height,uint256 reforacletxid,char *markeraddr,char *format); uint8_t DecodeOraclesCreateOpRet(const CScript &scriptPubKey,std::string &name,std::string &description,std::string &format); diff --git a/src/cc/CCutils.cpp b/src/cc/CCutils.cpp index cd7299bcf..c11ae2d3b 100644 --- a/src/cc/CCutils.cpp +++ b/src/cc/CCutils.cpp @@ -181,6 +181,16 @@ bool Getscriptaddress(char *destaddr,const CScript &scriptPubKey) return(false); } +CPubKey CCtxidaddr(char *txidaddr,uint256 txid) +{ + uint8_t buf33[33]; CPubKey pk; + buf33[0] = 0x02; + endiancpy(&buf33[1],(uint8_t *)&txid,32); + pk = buf2pk(buf33); + Getscriptaddress(coinaddr,CScript() << ParseHex(HexStr(pk)) << OP_CHECKSIG); + return(pk); +} + bool _GetCCaddress(char *destaddr,uint8_t evalcode,CPubKey pk) { CC *payoutCond; diff --git a/src/cc/gateways.cpp b/src/cc/gateways.cpp index 48927cb7d..9c7bdd35d 100644 --- a/src/cc/gateways.cpp +++ b/src/cc/gateways.cpp @@ -16,12 +16,11 @@ #include "CCGateways.h" /* - prevent duplicate bindtxid via mempool scan -claim needs to create a marker that is checked or validate deposittxid spending is ok + prevent duplicate bindtxid and cointxid via mempool scan assets vin selector needs to filter by signable vins -loop on merkle +loop on merkle oracle string oracles */ @@ -107,7 +106,7 @@ string oracles 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 gatewaysdeposit bindtxid height coin cointxid claimvout deposithex proof destpub amount numpks oraclepks -./komodo-cli -ac_name=AT5 gatewaysdeposit e6c99f79d4afb216aa8063658b4222edb773dd24bb0f8e91bd4ef341f3e47e5e 1003776 KMD bc41a00e429db741c3199f17546a48012fd3b7eea45dfc6bc2f5228278133009 0 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 proofhere 76a91447d2e323a14b0c3be08698aa46a9b91489b189d688ac 7.6999 1 02ebc786cb83de8dc3922ab83c21f3f8a2f3216940c3bf9da43ce39e2a3a882c92 +./komodo-cli -ac_name=AT5 gatewaysdeposit e6c99f79d4afb216aa8063658b4222edb773dd24bb0f8e91bd4ef341f3e47e5e 1003776 KMD bc41a00e429db741c3199f17546a48012fd3b7eea45dfc6bc2f5228278133009 0 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 76a91447d2e323a14b0c3be08698aa46a9b91489b189d688ac 7.6999 1 02ebc786cb83de8dc3922ab83c21f3f8a2f3216940c3bf9da43ce39e2a3a882c92 -> acc58b4552c4696406b681eb853b0c9a80ef8f02e3ec0e7bbd407b9261ecba81 gatewaysclaim bindtxid coin deposittxid destpub amount @@ -214,7 +213,7 @@ bool GatewaysExactAmounts(struct CCcontract_info *cp,Eval* eval,const CTransacti else return(true); } -bool GatewaysValidate(struct CCcontract_info *cp,Eval* eval,const CTransaction &tx) +bool GatewaysValidate(struct CCcontract_info *cp,Eval *eval,const CTransaction &tx) { int32_t numvins,numvouts,preventCCvins,preventCCvouts,i,numblocks; bool retval; uint256 txid; uint8_t hash[32]; char str[65],destaddr[64]; std::vector > txids; @@ -284,6 +283,44 @@ int64_t AddGatewaysInputs(struct CCcontract_info *cp,CMutableTransaction &mtx,CP return(totalinputs); } +int32_t GatewaysBindExists(struct CCcontract_info *cp,CPubKey gatewayspk,uint256 reftokenid) // dont forget to check mempool! +{ + char markeraddr[64]; std::string coin; int32_t numvouts; int64_t totalsupply; uint256 oracletxid,hashBlock; uint8_t M,N,taddr,prefix,prefix2; std::vector pubkeys; + std::vector > addressIndex; + _GetCCaddress(markeraddr,EVAL_GATEWAYS,gatewayspk); + fprintf(stderr,"bind markeraddr.(%s) need to scan mempool also\n",markeraddr); + SetCCtxids(addressIndex,markeraddr); + for (std::vector >::const_iterator it=addressIndex.begin(); it!=addressIndex.end(); it++) + { + if ( GetTransaction(it->first.txhash,tx,hashBlock,false) != 0 && (numvouts= tx.vout.size()) > 0 ) + { + if ( DecodeGatewaysBindOpRet(tx.vout[numvouts-1].scriptPubKey,coin,tokenid,totalsupply,oracletxid,M,N,pubkeys,taddr,prefix,prefix2) == 'B' ) + { + if ( tokenid == reftokenid ) + { + fprintf(stderr,"trying to bind an existing tokenid\n"); + return(1); + } + } + } + } + return(0); +} + +int32_t GatewaysCointxidExists(struct CCcontract_info *cp,uint256 cointxid) // dont forget to check mempool! +{ + char txidaddr[64]; std::string coin; int32_t numvouts; uint256 hashBlock; + std::vector > addressIndex; + CCtxidaddr(txidaddr,cointxid); + fprintf(stderr," txidaddr.(%s) need to scan mempool also\n",txidaddr); + SetCCtxids(addressIndex,txidaddr); + for (std::vector >::const_iterator it=addressIndex.begin(); it!=addressIndex.end(); it++) + { + return(-1); + } + return(0); +} + UniValue GatewaysInfo(uint256 bindtxid) { UniValue result(UniValue::VOBJ),a(UniValue::VARR); std::string coin; char str[67],numstr[65],depositaddr[64],gatewaysassets[64]; uint8_t M,N; std::vector pubkeys; uint8_t taddr,prefix,prefix2; uint256 tokenid,oracletxid,hashBlock; CTransaction tx; CMutableTransaction mtx; CPubKey Gatewayspk; struct CCcontract_info *cp,C; int32_t i; int64_t totalsupply,remaining; @@ -408,12 +445,11 @@ std::string GatewaysBind(uint64_t txfee,std::string coin,uint256 tokenid,int64_t fprintf(stderr,"illegal format (%s) != (%s)\n",fstr,(char *)"Ihh"); return(""); } - fprintf(stderr,"implement GatewaysBindExists\n"); - /*if ( GatewaysBindExists(cp,gatewayspk,coin,tokenid) != 0 ) // dont forget to check mempool! + if ( GatewaysBindExists(cp,gatewayspk,tokenid) != 0 ) // dont forget to check mempool! { fprintf(stderr,"Gateway bind.%s (%s) already exists\n",coin.c_str(),uint256_str(str,tokenid)); return(""); - }*/ + } if ( AddNormalinputs(mtx,mypk,2*txfee,60) > 0 ) { mtx.vout.push_back(MakeCC1vout(cp->evalcode,txfee,gatewayspk)); @@ -521,7 +557,7 @@ int64_t GatewaysDepositval(CTransaction tx) std::string GatewaysDeposit(uint64_t txfee,uint256 bindtxid,std::vectorpubkeys,int32_t height,std::string refcoin,uint256 cointxid,int32_t claimvout,std::string deposithex,std::vectorproof,CPubKey destpub,int64_t amount) { - CMutableTransaction mtx; CTransaction bindtx; CPubKey mypk,gatewayspk; uint256 oracletxid,merkleroot,mhash,hashBlock,tokenid,txid; int64_t totalsupply; int32_t i,m,n,numvouts; uint8_t M,N,taddr,prefix,prefix2; std::string coin; struct CCcontract_info *cp,C; std::vector msigpubkeys,publishers; std::vectortxids; char str[65],depositaddr[64]; + CMutableTransaction mtx; CTransaction bindtx; CPubKey mypk,gatewayspk; uint256 oracletxid,merkleroot,mhash,hashBlock,tokenid,txid; int64_t totalsupply; int32_t i,m,n,numvouts; uint8_t M,N,taddr,prefix,prefix2; std::string coin; struct CCcontract_info *cp,C; std::vector msigpubkeys,publishers; std::vectortxids; char str[65],depositaddr[64],txidaddr[64]; cp = CCinit(&C,EVAL_GATEWAYS); if ( txfee == 0 ) txfee = 10000; @@ -538,6 +574,11 @@ std::string GatewaysDeposit(uint64_t txfee,uint256 bindtxid,std::vector fprintf(stderr,"invalid bindtxid %s coin.%s\n",uint256_str(str,bindtxid),coin.c_str()); return(""); } + if ( GatewaysCointxidExists(cp,cointxid) != 0 ) + { + fprintf(stderr,"cointxid.%s already exists\n",uint256_str(str,cointxid)); + return(""); + } n = (int32_t)pubkeys.size(); merkleroot = zeroid; for (i=m=0; i fprintf(stderr,"deposittxid didnt validate\n"); return(""); } - if ( AddNormalinputs(mtx,mypk,2*txfee,60) > 0 ) + if ( AddNormalinputs(mtx,mypk,3*txfee,60) > 0 ) { mtx.vout.push_back(MakeCC1vout(cp->evalcode,txfee,mypk)); + mtx.vout.push_back(CTxOut(txfee,CScript() << ParseHex(HexStr(CCtxidaddr(txidaddr,cointxid))) << OP_CHECKSIG)); return(FinalizeCCTx(0,cp,mtx,mypk,txfee,EncodeGatewaysOpRet('D',coin,bindtxid,publishers,txids,height,cointxid,deposithex,proof,destpub,amount))); } fprintf(stderr,"cant find enough inputs\n"); diff --git a/src/cc/oracles.cpp b/src/cc/oracles.cpp index 2fa5e5815..82e1d4ab0 100644 --- a/src/cc/oracles.cpp +++ b/src/cc/oracles.cpp @@ -223,16 +223,12 @@ int64_t OracleCurrentDatafee(uint256 reforacletxid,char *markeraddr,CPubKey publ int64_t OracleDatafee(CScript &scriptPubKey,uint256 oracletxid,CPubKey publisher) { - CTransaction oracletx; char markeraddr[64]; CPubKey markerpubkey; uint8_t buf33[33]; uint256 hashBlock; std::string name,description,format; int32_t numvouts; int64_t datafee = 0; + CTransaction oracletx; char markeraddr[64]; uint256 hashBlock; std::string name,description,format; int32_t numvouts; int64_t datafee = 0; if ( myGetTransaction(oracletxid,oracletx,hashBlock) != 0 && (numvouts= oracletx.vout.size()) > 0 ) { if ( DecodeOraclesCreateOpRet(oracletx.vout[numvouts-1].scriptPubKey,name,description,format) == 'C' ) { - buf33[0] = 0x02; - endiancpy(&buf33[1],(uint8_t *)&oracletxid,32); - markerpubkey = buf2pk(buf33); - scriptPubKey = CScript() << ParseHex(HexStr(markerpubkey)) << OP_CHECKSIG; - Getscriptaddress(markeraddr,scriptPubKey); + CCtxidaddr(markeraddr,oracletxid); datafee = OracleCurrentDatafee(oracletxid,markeraddr,publisher); } } @@ -484,13 +480,10 @@ int64_t OraclePrice(int32_t height,uint256 reforacletxid,char *markeraddr,char * uint256 OraclesBatontxid(uint256 reforacletxid,CPubKey refpk) { std::vector > unspentOutputs; - CTransaction tx; uint256 hash,txid,rettxid,oracletxid; CPubKey pk,markerpubkey; int32_t numvouts,maxheight=0; int64_t datafee,ht; uint8_t buf33[33]; char markeraddr[64]; std::vector data; struct CCcontract_info *cp,C; + CTransaction tx; uint256 hash,txid,rettxid,oracletxid; CPubKey pk; int32_t numvouts,maxheight=0; int64_t datafee,ht; char markeraddr[64]; std::vector data; struct CCcontract_info *cp,C; rettxid = zeroid; cp = CCinit(&C,EVAL_ORACLES); - buf33[0] = 0x02; - endiancpy(&buf33[1],(uint8_t *)&reforacletxid,32); - markerpubkey = buf2pk(buf33); - Getscriptaddress(markeraddr,CScript() << ParseHex(HexStr(markerpubkey)) << OP_CHECKSIG); + CCtxidaddr(markeraddr,reforacletxid); SetCCunspents(unspentOutputs,markeraddr); for (std::vector >::const_iterator it=unspentOutputs.begin(); it!=unspentOutputs.end(); it++) { @@ -721,7 +714,7 @@ std::string OracleCreate(int64_t txfee,std::string name,std::string description, std::string OracleRegister(int64_t txfee,uint256 oracletxid,int64_t datafee) { - CMutableTransaction mtx; CPubKey mypk,markerpubkey,batonpk; struct CCcontract_info *cp,C; uint8_t buf33[33]; char markeraddr[64],batonaddr[64]; + CMutableTransaction mtx; CPubKey mypk,markerpubkey,batonpk; struct CCcontract_info *cp,C; char markeraddr[64],batonaddr[64]; cp = CCinit(&C,EVAL_ORACLES); if ( txfee == 0 ) txfee = 10000; @@ -731,11 +724,8 @@ std::string OracleRegister(int64_t txfee,uint256 oracletxid,int64_t datafee) return(""); } mypk = pubkey2pk(Mypubkey()); - buf33[0] = 0x02; - endiancpy(&buf33[1],(uint8_t *)&oracletxid,32); - markerpubkey = buf2pk(buf33); - Getscriptaddress(markeraddr,CScript() << ParseHex(HexStr(markerpubkey)) << OP_CHECKSIG); batonpk = OracleBatonPk(batonaddr,cp); + markerpubkey = CCtxidaddr(markeraddr,oracletxid); if ( AddNormalinputs(mtx,mypk,3*txfee,4) > 0 ) { mtx.vout.push_back(CTxOut(txfee,CScript() << ParseHex(HexStr(markerpubkey)) << OP_CHECKSIG)); @@ -747,15 +737,12 @@ std::string OracleRegister(int64_t txfee,uint256 oracletxid,int64_t datafee) std::string OracleSubscribe(int64_t txfee,uint256 oracletxid,CPubKey publisher,int64_t amount) { - CMutableTransaction mtx; CPubKey mypk,markerpubkey; struct CCcontract_info *cp,C; uint8_t buf33[33]; char markeraddr[64]; + CMutableTransaction mtx; CPubKey mypk,markerpubkey; struct CCcontract_info *cp,C; char markeraddr[64]; cp = CCinit(&C,EVAL_ORACLES); if ( txfee == 0 ) txfee = 10000; mypk = pubkey2pk(Mypubkey()); - buf33[0] = 0x02; - endiancpy(&buf33[1],(uint8_t *)&oracletxid,32); - markerpubkey = buf2pk(buf33); - Getscriptaddress(markeraddr,CScript() << ParseHex(HexStr(markerpubkey)) << OP_CHECKSIG); + markerpubkey = CCtxidaddr(markeraddr,oracletxid); if ( AddNormalinputs(mtx,mypk,amount + 2*txfee,1) > 0 ) { mtx.vout.push_back(MakeCC1vout(cp->evalcode,amount,publisher)); @@ -849,12 +836,9 @@ UniValue OracleInfo(uint256 origtxid) { UniValue result(UniValue::VOBJ),a(UniValue::VARR),obj(UniValue::VOBJ); std::vector > unspentOutputs; - CMutableTransaction mtx; CTransaction regtx,tx; std::string name,description,format; uint256 hashBlock,txid,oracletxid,batontxid; CPubKey markerpubkey,pk; struct CCcontract_info *cp,C; uint8_t buf33[33]; int64_t datafee,funding; char str[67],markeraddr[64],numstr[64],batonaddr[64]; std::vector data; + CMutableTransaction mtx; CTransaction regtx,tx; std::string name,description,format; uint256 hashBlock,txid,oracletxid,batontxid; CPubKey pk; struct CCcontract_info *cp,C; int64_t datafee,funding; char str[67],markeraddr[64],numstr[64],batonaddr[64]; std::vector data; cp = CCinit(&C,EVAL_ORACLES); - buf33[0] = 0x02; - endiancpy(&buf33[1],(uint8_t *)&origtxid,32); - markerpubkey = buf2pk(buf33); - Getscriptaddress(markeraddr,CScript() << ParseHex(HexStr(markerpubkey)) << OP_CHECKSIG); + CCtxidaddr(markeraddr,origtxid); if ( GetTransaction(origtxid,tx,hashBlock,false) != 0 ) { if ( tx.vout.size() > 0 && DecodeOraclesCreateOpRet(tx.vout[tx.vout.size()-1].scriptPubKey,name,description,format) == 'C' )