path: root/common/registrar/ethreg/api.go

// Copyright 2015 The go-ethereum Authors
// This file is part of the go-ethereum library.
//
// The go-ethereum library is free software: you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// The go-ethereum library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.

package ethreg

import (
    "errors"
    "math/big"

    "github.com/ethereum/go-ethereum/accounts"
    "github.com/ethereum/go-ethereum/common"
    "github.com/ethereum/go-ethereum/common/compiler"
    "github.com/ethereum/go-ethereum/common/registrar"
    "github.com/ethereum/go-ethereum/core"
    "github.com/ethereum/go-ethereum/core/state"
    "github.com/ethereum/go-ethereum/core/types"
    "github.com/ethereum/go-ethereum/crypto"
    "github.com/ethereum/go-ethereum/ethdb"
    "github.com/ethereum/go-ethereum/logger"
    "github.com/ethereum/go-ethereum/logger/glog"
)

// registryAPIBackend is a backend for an Ethereum Registry.
type registryAPIBackend struct {
    bc      *core.BlockChain
    chainDb ethdb.Database
    txPool  *core.TxPool
    am      *accounts.Manager
}

// PrivateRegistarAPI offers various functions to access the Ethereum registry.
type PrivateRegistarAPI struct {
    be *registryAPIBackend
}

// NewPrivateRegistarAPI creates a new PrivateRegistarAPI instance.
func NewPrivateRegistarAPI(bc *core.BlockChain, chainDb ethdb.Database, txPool *core.TxPool, am *accounts.Manager) *PrivateRegistarAPI {
    return &PrivateRegistarAPI{&registryAPIBackend{bc, chainDb, txPool, am}}
}

// SetGlobalRegistrar allows clients to set the global registry for the node.
// This method can be used to deploy a new registry. First zero out the current
// address by calling the method with namereg = '0x0' and then call this method
// again with '' as namereg. This will submit a transaction to the network which
// will deploy a new registry on execution. The TX hash is returned. When called
// with namereg '' and the current address is not zero the current global is
// address is returned..
func (api *PrivateRegistarAPI) SetGlobalRegistrar(namereg string, from common.Address) (string, error) {
    return registrar.New(api.be).SetGlobalRegistrar(namereg, from)
}

// SetHashReg queries the registry for a hash.
func (api *PrivateRegistarAPI) SetHashReg(hashreg string, from common.Address) (string, error) {
    return registrar.New(api.be).SetHashReg(hashreg, from)
}

// SetUrlHint queries the registry for an url.
func (api *PrivateRegistarAPI) SetUrlHint(hashreg string, from common.Address) (string, error) {
    return registrar.New(api.be).SetUrlHint(hashreg, from)
}

// SaveInfo stores contract information on the local file system.
func (api *PrivateRegistarAPI) SaveInfo(info *compiler.ContractInfo, filename string) (contenthash common.Hash, err error) {
    return compiler.SaveInfo(info, filename)
}

// Register registers a new content hash in the registry.
func (api *PrivateRegistarAPI) Register(sender common.Address, addr common.Address, contentHashHex string) (bool, error) {
    block := api.be.bc.CurrentBlock()
    state, err := state.New(block.Root(), api.be.chainDb)
    if err != nil {
        return false, err
    }

    codeb := state.GetCode(addr)
    codeHash := common.BytesToHash(crypto.Sha3(codeb))
    contentHash := common.HexToHash(contentHashHex)

    _, err = registrar.New(api.be).SetHashToHash(sender, codeHash, contentHash)
    return err == nil, err
}

// RegisterUrl registers a new url in the registry.
func (api *PrivateRegistarAPI) RegisterUrl(sender common.Address, contentHashHex string, url string) (bool, error) {
    _, err := registrar.New(api.be).SetUrlToHash(sender, common.HexToHash(contentHashHex), url)
    return err == nil, err
}

// callmsg is the message type used for call transations.
type callmsg struct {
    from          *state.StateObject
    to            *common.Address
    gas, gasPrice *big.Int
    value         *big.Int
    data          []byte
}

// accessor boilerplate to implement core.Message
func (m callmsg) From() (common.Address, error) {
    return m.from.Address(), nil
}
func (m callmsg) FromFrontier() (common.Address, error) {
    return m.from.Address(), nil
}
func (m callmsg) Nonce() uint64 {
    return m.from.Nonce()
}
func (m callmsg) To() *common.Address {
    return m.to
}
func (m callmsg) GasPrice() *big.Int {
    return m.gasPrice
}
func (m callmsg) Gas() *big.Int {
    return m.gas
}
func (m callmsg) Value() *big.Int {
    return m.value
}
func (m callmsg) Data() []byte {
    return m.data
}

// Call forms a transaction from the given arguments and tries to execute it on
// a private VM with a copy of the state. Any changes are therefore only temporary
// and not part of the actual state. This allows for local execution/queries.
func (be *registryAPIBackend) Call(fromStr, toStr, valueStr, gasStr, gasPriceStr, dataStr string) (string, string, error) {
    block := be.bc.CurrentBlock()
    statedb, err := state.New(block.Root(), be.chainDb)
    if err != nil {
        return "", "", err
    }

    var from *state.StateObject
    if len(fromStr) == 0 {
        accounts, err := be.am.Accounts()
        if err != nil || len(accounts) == 0 {
            from = statedb.GetOrNewStateObject(common.Address{})
        } else {
            from = statedb.GetOrNewStateObject(accounts[0].Address)
        }
    } else {
        from = statedb.GetOrNewStateObject(common.HexToAddress(fromStr))
    }

    from.SetBalance(common.MaxBig)

    msg := callmsg{
        from:     from,
        gas:      common.Big(gasStr),
        gasPrice: common.Big(gasPriceStr),
        value:    common.Big(valueStr),
        data:     common.FromHex(dataStr),
    }
    if len(toStr) > 0 {
        addr := common.HexToAddress(toStr)
        msg.to = &addr
    }

    if msg.gas.Cmp(big.NewInt(0)) == 0 {
        msg.gas = big.NewInt(50000000)
    }

    if msg.gasPrice.Cmp(big.NewInt(0)) == 0 {
        msg.gasPrice = new(big.Int).Mul(big.NewInt(50), common.Shannon)
    }

    header := be.bc.CurrentBlock().Header()
    vmenv := core.NewEnv(statedb, be.bc, msg, header)
    gp := new(core.GasPool).AddGas(common.MaxBig)
    res, gas, err := core.ApplyMessage(vmenv, msg, gp)

    return common.ToHex(res), gas.String(), err
}

// StorageAt returns the data stores in the state for the given address and location.
func (be *registryAPIBackend) StorageAt(addr string, storageAddr string) string {
    block := be.bc.CurrentBlock()
    state, err := state.New(block.Root(), be.chainDb)
    if err != nil {
        return ""
    }
    return state.GetState(common.HexToAddress(addr), common.HexToHash(storageAddr)).Hex()
}

// Transact forms a transaction from the given arguments and submits it to the
// transactio pool for execution.
func (be *registryAPIBackend) Transact(fromStr, toStr, nonceStr, valueStr, gasStr, gasPriceStr, codeStr string) (string, error) {
    if len(toStr) > 0 && toStr != "0x" && !common.IsHexAddress(toStr) {
        return "", errors.New("invalid address")
    }

    var (
        from             = common.HexToAddress(fromStr)
        to               = common.HexToAddress(toStr)
        value            = common.Big(valueStr)
        gas              *big.Int
        price            *big.Int
        data             []byte
        contractCreation bool
    )

    if len(gasStr) == 0 {
        gas = big.NewInt(90000)
    } else {
        gas = common.Big(gasStr)
    }

    if len(gasPriceStr) == 0 {
        price = big.NewInt(10000000000000)
    } else {
        price = common.Big(gasPriceStr)
    }

    data = common.FromHex(codeStr)
    if len(toStr) == 0 {
        contractCreation = true
    }

    nonce := be.txPool.State().GetNonce(from)
    if len(nonceStr) != 0 {
        nonce = common.Big(nonceStr).Uint64()
    }

    var tx *types.Transaction
    if contractCreation {
        tx = types.NewContractCreation(nonce, value, gas, price, data)
    } else {
        tx = types.NewTransaction(nonce, to, value, gas, price, data)
    }

    acc := accounts.Account{from}
    signature, err := be.am.Sign(acc, tx.SigHash().Bytes())
    if err != nil {
        return "", err
    }
    signedTx, err := tx.WithSignature(signature)
    if err != nil {
        return "", err
    }

    be.txPool.SetLocal(signedTx)
    if err := be.txPool.Add(signedTx); err != nil {
        return "", nil
    }

    if contractCreation {
        addr := crypto.CreateAddress(from, nonce)
        glog.V(logger.Info).Infof("Tx(%s) created: %s\n", signedTx.Hash().Hex(), addr.Hex())
    } else {
        glog.V(logger.Info).Infof("Tx(%s) to: %s\n", signedTx.Hash().Hex(), tx.To().Hex())
    }

    return signedTx.Hash().Hex(), nil
}