pragma solidity ^0.4.11; /* Copyright 2017, Jordi Baylina Contributor: AdriĆ  Massanet This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version. This program 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 General Public License for more details. You should have received a copy of the GNU General Public License along with this program. If not, see . */ // Contract Imports import "./LiquidPledgingBase.sol"; /// @dev `LiquidPleding` allows for liquid pledging through the use of /// internal id structures and delegate chaining. All basic operations for /// handling liquid pledging are supplied as well as plugin features /// to allow for expanded functionality. contract LiquidPledging is LiquidPledgingBase { ////// // Constructor ////// /// @notice Basic constructor for LiquidPleding, also calls the /// LiquidPledgingBase contract /// @dev This constructor also calls the constructor /// for `LiquidPledgingBase` /// @param _vault The vault where ETH backing this pledge is stored function LiquidPledging(address _vault) LiquidPledgingBase(_vault) { } /// @notice This is how value enters into the system which creates pledges; /// the token of value goes into the vault and the amount in the pledge /// relevant to this Giver without delegates is increased, and a normal /// transfer is done to the idReceiver /// @param idGiver Identifier of the giver thats donating. /// @param idReceiver To whom it's transfered. Can be the same giver, /// another giver, a delegate or a project. function donate(uint64 idGiver, uint64 idReceiver) payable { if (idGiver == 0) { // default to 3 day commitTime idGiver = addGiver("", "", 259200, ILiquidPledgingPlugin(0x0)); } PledgeAdmin storage sender = findAdmin(idGiver); checkAdminOwner(sender); require(sender.adminType == PledgeAdminType.Giver); uint amount = msg.value; require(amount > 0); vault.transfer(amount); // transfers the baseToken to the Vault uint64 idPledge = findOrCreatePledge( idGiver, new uint64[](0), //what is new? 0, 0, 0, PaymentState.Pledged ); Pledge storage nTo = findPledge(idPledge); nTo.amount += amount; Transfer(0, idPledge, amount); transfer(idGiver, idPledge, amount, idReceiver); } /// @notice Moves value between pledges /// @param idSender ID of the giver, delegate or project admin that is /// transferring the funds from Pledge to Pledge; this admin must have /// permissions to move the value /// @param idPledge Id of the pledge that's moving the value /// @param amount Quantity of value that's being moved /// @param idReceiver Destination of the value, can be a giver sending to /// a giver or a delegate, a delegate to another delegate or a project /// to pre-commit it to that project if called from a delegate, /// or to commit it to the project if called from the owner. function transfer( uint64 idSender, uint64 idPledge, uint amount, uint64 idReceiver ) { idPledge = normalizePledge(idPledge); Pledge storage n = findPledge(idPledge); PledgeAdmin storage receiver = findAdmin(idReceiver); PledgeAdmin storage sender = findAdmin(idSender); checkAdminOwner(sender); require(n.paymentState == PaymentState.Pledged); // If the sender is the owner if (n.owner == idSender) { if (receiver.adminType == PledgeAdminType.Giver) { transferOwnershipToGiver(idPledge, amount, idReceiver); } else if (receiver.adminType == PledgeAdminType.Project) { transferOwnershipToProject(idPledge, amount, idReceiver); } else if (receiver.adminType == PledgeAdminType.Delegate) { uint recieverDIdx = getDelegateIdx(n, idReceiver); if (n.intendedProject > 0 && recieverDIdx != NOTFOUND) { // if there is an intendedProject and the receiver is in the delegationChain, // then we want to preserve the delegationChain as this is a veto of the // intendedProject by the owner if (recieverDIdx == n.delegationChain.length - 1) { uint64 toPledge = findOrCreatePledge( n.owner, n.delegationChain, 0, 0, n.oldPledge, PaymentState.Pledged); doTransfer(idPledge, toPledge, amount); } else { undelegate(idPledge, amount, n.delegationChain.length - receiverDIdx - 1); } } else { // owner is not vetoing an intendedProject and is transferring the pledge to a delegate, // so we want to reset the delegationChain idPledge = undelegate(idPledge, amount, n.delegationChain.length); appendDelegate(idPledge, amount, idReceiver); } } else { assert(false); } return; } // If the sender is a delegate uint senderDIdx = getDelegateIdx(n, idSender); if (senderDIdx != NOTFOUND) { // If the receiver is another giver if (receiver.adminType == PledgeAdminType.Giver) { // Only accept to change to the original giver to // remove all delegates assert(n.owner == idReceiver); undelegate(idPledge, amount, n.delegationChain.length); return; } // If the receiver is another delegate if (receiver.adminType == PledgeAdminType.Delegate) { uint receiverDIdx = getDelegateIdx(n, idReceiver); // If the receiver is not in the delegate list if (receiverDIdx == NOTFOUND) { idPledge = undelegate( idPledge, amount, n.delegationChain.length - senderDIdx - 1 ); appendDelegate(idPledge, amount, idReceiver); // If the receiver is already part of the delegate chain and is // after the sender, then all of the other delegates after the // sender are removed and the receiver is appended at the // end of the delegation chain } else if (receiverDIdx > senderDIdx) { idPledge = undelegate( idPledge, amount, n.delegationChain.length - senderDIdx - 1 ); appendDelegate(idPledge, amount, idReceiver); // If the receiver is already part of the delegate chain and is // before the sender, then the sender and all of the other // delegates after the RECEIVER are removed from the chain, // this is interesting because the delegate is removed from the // delegates that delegated to this delegate. Are there game theory // issues? should this be allowed? } else if (receiverDIdx <= senderDIdx) { undelegate( idPledge, amount, n.delegationChain.length - receiverDIdx - 1 ); } return; } // If the delegate wants to support a project, they remove all // the delegates after them in the chain and choose a project if (receiver.adminType == PledgeAdminType.Project) { idPledge = undelegate( idPledge, amount, n.delegationChain.length - senderDIdx - 1 ); proposeAssignProject(idPledge, amount, idReceiver); return; } } assert(false); // It is not the owner nor any delegate. } /// @notice This method is used to withdraw value from the system. /// This can be used by the givers withdraw any un-commited donations. /// @param idPledge Id of the pledge that wants to be withdrawn. /// @param amount Quantity of Ether that wants to be withdrawn. function withdraw(uint64 idPledge, uint amount) { idPledge = normalizePledge(idPledge); Pledge storage n = findPledge(idPledge); require(n.paymentState == PaymentState.Pledged); PledgeAdmin storage owner = findAdmin(n.owner); checkAdminOwner(owner); uint64 idNewPledge = findOrCreatePledge( n.owner, n.delegationChain, 0, 0, n.oldPledge, PaymentState.Paying ); doTransfer(idPledge, idNewPledge, amount); vault.authorizePayment(bytes32(idNewPledge), owner.addr, amount); } /// @notice Method called by the vault to confirm a payment. /// @param idPledge Id of the pledge that wants to be withdrawn. /// @param amount Quantity of Ether that wants to be withdrawn. function confirmPayment(uint64 idPledge, uint amount) onlyVault { Pledge storage n = findPledge(idPledge); require(n.paymentState == PaymentState.Paying); uint64 idNewPledge = findOrCreatePledge( n.owner, n.delegationChain, 0, 0, n.oldPledge, PaymentState.Paid ); doTransfer(idPledge, idNewPledge, amount); } /// @notice Method called by the vault to cancel a payment. /// @param idPledge Id of the pledge that wants to be canceled for withdraw. /// @param amount Quantity of Ether that wants to be rolled back. function cancelPayment(uint64 idPledge, uint amount) onlyVault { Pledge storage n = findPledge(idPledge); require(n.paymentState == PaymentState.Paying); //TODO change to revert // When a payment is canceled, never is assigned to a project. uint64 oldPledge = findOrCreatePledge( n.owner, n.delegationChain, 0, 0, n.oldPledge, PaymentState.Pledged ); oldPledge = normalizePledge(oldPledge); doTransfer(idPledge, oldPledge, amount); } /// @notice Method called to cancel this project. /// @param idProject Id of the projct that wants to be canceled. function cancelProject(uint64 idProject) { PledgeAdmin storage project = findAdmin(idProject); checkAdminOwner(project); project.canceled = true; CancelProject(idProject); } /// @notice Method called to cancel specific pledge. /// @param idPledge Id of the pledge that should be canceled. /// @param amount Quantity of Ether that wants to be rolled back. function cancelPledge(uint64 idPledge, uint amount) { idPledge = normalizePledge(idPledge); Pledge storage n = findPledge(idPledge); require(n.oldPledge != 0); PledgeAdmin storage m = findAdmin(n.owner); checkAdminOwner(m); uint64 oldPledge = getOldestPledgeNotCanceled(n.oldPledge); doTransfer(idPledge, oldPledge, amount); } //////// // Multi pledge methods //////// // @dev This set of functions makes moving a lot of pledges around much more // efficient (saves gas) than calling these functions in series /// Bit mask used for dividing pledge amounts in Multi pledge methods uint constant D64 = 0x10000000000000000; /// @notice `mTransfer` allows for multiple pledges to be transferred /// efficiently /// @param idSender ID of the giver, delegate or project admin that is /// transferring the funds from Pledge to Pledge. This admin must have /// permissions to move the value /// @param pledgesAmounts An array of pledge amounts and IDs which are extrapolated /// using the D64 bitmask /// @param idReceiver Destination of the value, can be a giver sending /// to a giver or a delegate or a delegate to another delegate or a /// project to pre-commit it to that project function mTransfer( uint64 idSender, uint[] pledgesAmounts, uint64 idReceiver ) { for (uint i = 0; i < pledgesAmounts.length; i++ ) { uint64 idPledge = uint64( pledgesAmounts[i] & (D64-1) ); uint amount = pledgesAmounts[i] / D64; transfer(idSender, idPledge, amount, idReceiver); } } /// @notice `mWithdraw` allows for multiple pledges to be /// withdrawn efficiently /// @param pledgesAmounts An array of pledge amounts and IDs which are /// extrapolated using the D64 bitmask function mWithdraw(uint[] pledgesAmounts) { for (uint i = 0; i < pledgesAmounts.length; i++ ) { uint64 idPledge = uint64( pledgesAmounts[i] & (D64-1) ); uint amount = pledgesAmounts[i] / D64; withdraw(idPledge, amount); } } /// @notice `mConfirmPayment` allows for multiple pledges to be confirmed /// efficiently /// @param pledgesAmounts An array of pledge amounts and IDs which are extrapolated /// using the D64 bitmask function mConfirmPayment(uint[] pledgesAmounts) { for (uint i = 0; i < pledgesAmounts.length; i++ ) { uint64 idPledge = uint64( pledgesAmounts[i] & (D64-1) ); uint amount = pledgesAmounts[i] / D64; confirmPayment(idPledge, amount); } } /// @notice `mCancelPayment` allows for multiple pledges to be canceled /// efficiently /// @param pledgesAmounts An array of pledge amounts and IDs which are extrapolated /// using the D64 bitmask function mCancelPayment(uint[] pledgesAmounts) { for (uint i = 0; i < pledgesAmounts.length; i++ ) { uint64 idPledge = uint64( pledgesAmounts[i] & (D64-1) ); uint amount = pledgesAmounts[i] / D64; cancelPayment(idPledge, amount); } } /// @notice `mNormalizePledge` allows for multiple pledges to be /// normalized efficiently /// @param pledges An array of pledge IDs function mNormalizePledge(uint64[] pledges) { for (uint i = 0; i < pledges.length; i++ ) { normalizePledge( pledges[i] ); } } //////// // Private methods /////// /// @notice `transferOwnershipToProject` allows for the transfer of /// ownership to the project, but it can also be called by a project /// to un-delegate everyone by setting one's own id for the idReceiver /// @param idPledge Id of the pledge to be transfered. /// @param amount Quantity of value that's being transfered /// @param idReceiver The new owner of the project (or self to un-delegate) function transferOwnershipToProject( uint64 idPledge, uint amount, uint64 idReceiver ) internal { Pledge storage n = findPledge(idPledge); // Ensure that the pledge is not already at max pledge depth // and the project has not been canceled require(getPledgeLevel(n) < MAX_INTERPROJECT_LEVEL); require(!isProjectCanceled(idReceiver)); uint64 oldPledge = findOrCreatePledge( n.owner, n.delegationChain, 0, 0, n.oldPledge, PaymentState.Pledged ); uint64 toPledge = findOrCreatePledge( idReceiver, // Set the new owner new uint64[](0), // clear the delegation chain 0, 0, oldPledge, PaymentState.Pledged ); doTransfer(idPledge, toPledge, amount); } /// @notice `transferOwnershipToGiver` allows for the transfer of /// value back to the Giver, value is placed in a pledged state /// without being attached to a project, delegation chain, or time line. /// @param idPledge Id of the pledge to be transfered. /// @param amount Quantity of value that's being transfered /// @param idReceiver The new owner of the pledge function transferOwnershipToGiver( uint64 idPledge, uint amount, uint64 idReceiver ) internal { uint64 toPledge = findOrCreatePledge( idReceiver, new uint64[](0), 0, 0, 0, PaymentState.Pledged ); doTransfer(idPledge, toPledge, amount); } /// @notice `appendDelegate` allows for a delegate to be added onto the /// end of the delegate chain for a given Pledge. /// @param idPledge Id of the pledge thats delegate chain will be modified. /// @param amount Quantity of value that's being chained. /// @param idReceiver The delegate to be added at the end of the chain function appendDelegate( uint64 idPledge, uint amount, uint64 idReceiver ) internal { Pledge storage n = findPledge(idPledge); require(n.delegationChain.length < MAX_DELEGATES); uint64[] memory newDelegationChain = new uint64[]( n.delegationChain.length + 1 ); for (uint i = 0; i= amount); nFrom.amount -= amount; nTo.amount += amount; Transfer(from, to, amount); callPlugins(false, from, to, amount); } /// @notice `normalizePledge` only affects pledges with the Pledged PaymentState /// and does 2 things: /// #1: Checks if the pledge should be committed. This means that /// if the pledge has an intendedProject and it is past the /// commitTime, it changes the owner to be the proposed project /// (The UI will have to read the commit time and manually do what /// this function does to the pledge for the end user /// at the expiration of the commitTime) /// /// #2: Checks to make sure that if there has been a cancellation in the /// chain of projects, the pledge's owner has been changed /// appropriately. /// /// This function can be called by anybody at anytime on any pledge. /// In general it can be called to force the calls of the affected /// plugins, which also need to be predicted by the UI /// @param idPledge This is the id of the pledge that will be normalized function normalizePledge(uint64 idPledge) returns(uint64) { Pledge storage n = findPledge(idPledge); // Check to make sure this pledge hasn't already been used // or is in the process of being used if (n.paymentState != PaymentState.Pledged) { return idPledge; } // First send to a project if it's proposed and committed if ((n.intendedProject > 0) && ( getTime() > n.commitTime)) { uint64 oldPledge = findOrCreatePledge( n.owner, n.delegationChain, 0, 0, n.oldPledge, PaymentState.Pledged ); uint64 toPledge = findOrCreatePledge( n.intendedProject, new uint64[](0), 0, 0, oldPledge, PaymentState.Pledged ); doTransfer(idPledge, toPledge, n.amount); idPledge = toPledge; n = findPledge(idPledge); } toPledge = getOldestPledgeNotCanceled(idPledge);// TODO toPledge is pledge defined if (toPledge != idPledge) { doTransfer(idPledge, toPledge, n.amount); } return toPledge; } ///////////// // Plugins ///////////// /// @notice `callPlugin` is used to trigger the general functions in the /// plugin for any actions needed before and after a transfer happens. /// Specifically what this does in relation to the plugin is something /// that largely depends on the functions of that plugin. This function /// is generally called in pairs, once before, and once after a transfer. /// @param before This toggle determines whether the plugin call is occurring /// before or after a transfer. /// @param adminId This should be the Id of the *trusted* individual /// who has control over this plugin. /// @param fromPledge This is the Id from which value is being transfered. /// @param toPledge This is the Id that value is being transfered to. /// @param context The situation that is triggering the plugin. See plugin /// for a full description of contexts. /// @param amount The amount of value that is being transfered. function callPlugin( bool before, uint64 adminId, uint64 fromPledge, uint64 toPledge, uint64 context, uint amount ) internal returns (uint allowedAmount) { uint newAmount; allowedAmount = amount; PledgeAdmin storage admin = findAdmin(adminId); // Checks admin has a plugin assigned and a non-zero amount is requested if ((address(admin.plugin) != 0) && (allowedAmount > 0)) { // There are two seperate functions called in the plugin. // One is called before the transfer and one after if (before) { newAmount = admin.plugin.beforeTransfer( adminId, fromPledge, toPledge, context, amount ); require(newAmount <= allowedAmount); allowedAmount = newAmount; } else { admin.plugin.afterTransfer( adminId, fromPledge, toPledge, context, amount ); } } } /// @notice `callPluginsPledge` is used to apply plugin calls to /// the delegate chain and the intended project if there is one. /// It does so in either a transferring or receiving context based /// on the `idPledge` and `fromPledge` parameters. /// @param before This toggle determines whether the plugin call is occuring /// before or after a transfer. /// @param idPledge This is the Id of the pledge on which this plugin /// is being called. /// @param fromPledge This is the Id from which value is being transfered. /// @param toPledge This is the Id that value is being transfered to. /// @param amount The amount of value that is being transfered. function callPluginsPledge( bool before, uint64 idPledge, uint64 fromPledge, uint64 toPledge, uint amount ) internal returns (uint allowedAmount) { // Determine if callPlugin is being applied in a receiving // or transferring context uint64 offset = idPledge == fromPledge ? 0 : 256; allowedAmount = amount; Pledge storage n = findPledge(idPledge); // Always call the plugin on the owner allowedAmount = callPlugin( before, n.owner, fromPledge, toPledge, offset, allowedAmount ); // Apply call plugin to all delegates for (uint64 i=0; i 0) { allowedAmount = callPlugin( before, n.intendedProject, fromPledge, toPledge, offset + 255, allowedAmount ); } } /// @notice `callPlugins` calls `callPluginsPledge` once for the transfer /// context and once for the receiving context. The aggregated /// allowed amount is then returned. /// @param before This toggle determines whether the plugin call is occuring /// before or after a transfer. /// @param fromPledge This is the Id from which value is being transfered. /// @param toPledge This is the Id that value is being transfered to. /// @param amount The amount of value that is being transfered. function callPlugins( bool before, uint64 fromPledge, uint64 toPledge, uint amount ) internal returns (uint allowedAmount) { allowedAmount = amount; // Call the pledges plugins in the transfer context allowedAmount = callPluginsPledge( before, fromPledge, fromPledge, toPledge, allowedAmount ); // Call the pledges plugins in the receive context allowedAmount = callPluginsPledge( before, toPledge, fromPledge, toPledge, allowedAmount ); } ///////////// // Test functions ///////////// /// @notice Basic helper function to return the current time function getTime() internal returns (uint) { return now; } // Event Delcerations event Transfer(uint64 indexed from, uint64 indexed to, uint amount); event CancelProject(uint64 indexed idProject); }