# OFMF跨链对接
# 比特币跨链
对比特币跨链是通过检查接收地址（多签地址）和OP_RETURN中的附加信息来确定的。对于OFMF系统而言，如果检测到交易输出中包含指定的接收地址，并且在附加信息中解码得到比原地址，这样便可以确定是一笔跨链请求交易。
跨链交易请求:
{
"jsonrpc":"2.0",
"method":"createrawtransaction",
"id":1,
"params":[
[
{
"txid":"79d2d49cee6a2b37838ac1f2b459f7820a4efdfb91a0d20417b835ae10dea801",
"vout":0
}
],
[
{
"2N5KvkLV9JzEqVeLpc7tG5LB9ZkzXB8xGLh":49 // 多签地址
},
{
"data":"0014ce6cf18e24407480b22fb086358e8071a672f62a" // 附加信息（包含比原的control_program）
},
{
"2NAj8SjSVhZL8iry9fRnzcKgp8VotL3T8R2":0.9 // 找零地址
}
]
]
}
跨链交易响应:
{
"result": "020000000101a8de10ae35b81704d2a091fbfd4e0a82f759b4f2c18a83372b6aee9cd4d2790000000000ffffffff03001110240100000017a91484853295a31883eb9b499f1616d5dfe595ba7650870000000000000000186a160014ce6cf18e24407480b22fb086358e8071a672f62a804a5d050000000017a914bfc128490ae2ee6b91da82fc762445eded61d8ae8700000000",
"error": null,
"id": 1
}
跨链交易详细信息:
{
"result": {
"txid": "3af30005081c1fe084872564ff7e1c75fda617c75f6e80987498ce5a84ac8262",
"hash": "3af30005081c1fe084872564ff7e1c75fda617c75f6e80987498ce5a84ac8262",
"version": 2,
"size": 148,
"vsize": 148,
"weight": 592,
"locktime": 0,
"vin": [
{
"txid": "79d2d49cee6a2b37838ac1f2b459f7820a4efdfb91a0d20417b835ae10dea801",
"vout": 0,
"scriptSig": {
"asm": "",
"hex": ""
},
"sequence": 4294967295
}
],
"vout": [
{
"value": 49.00000000,
"n": 0,
"scriptPubKey": {
"asm": "OP_HASH160 84853295a31883eb9b499f1616d5dfe595ba7650 OP_EQUAL",
"hex": "a91484853295a31883eb9b499f1616d5dfe595ba765087",
"reqSigs": 1,
"type": "scripthash",
"addresses": [
"2N5KvkLV9JzEqVeLpc7tG5LB9ZkzXB8xGLh"
]
}
},
{
"value": 0.00000000,
"n": 1,
"scriptPubKey": {
"asm": "OP_RETURN 0014ce6cf18e24407480b22fb086358e8071a672f62a", // OP_RETURN + 比原地址对应的control_program
"hex": "6a160014ce6cf18e24407480b22fb086358e8071a672f62a",
"type": "nulldata"
}
},
{
"value": 0.90000000,
"n": 2,
"scriptPubKey": {
"asm": "OP_HASH160 bfc128490ae2ee6b91da82fc762445eded61d8ae OP_EQUAL",
"hex": "a914bfc128490ae2ee6b91da82fc762445eded61d8ae87",
"reqSigs": 1,
"type": "scripthash",
"addresses": [
"2NAj8SjSVhZL8iry9fRnzcKgp8VotL3T8R2"
]
}
}
]
},
"error": null,
"id": 1
}
# 以太坊跨链
以太坊跨链是通过检测多签合约和比原地址注册合约两部分来构成的，为了以后兼容以太坊的ERC20系列币种，跨链到比原上的地址都通过注册合约的形式来获取。要构建一笔跨到OFMF系统的交易，首先需要调用注册合约将自己的发送地址跟比原地址绑定起来，然后再发送以太币ether到多签合约地址上。因此，用户只需要在第一次跨链的时候完成跨链地址的注册，便可以在以后的跨链过程中重复使用了。对于OFMF系统而言，如果检测到交易目标地址是多签合约，并且在注册合约中能够找到发送者注册的比原地址，这样便可以确定是一笔跨链请求交易。
转账到多签合约地址
跨链交易请求:(普通转账交易)
{
"jsonrpc":"2.0",
"method":"eth_sendTransaction",
"id":1,
"params":[
{
"from":"0x9ba9ae032a2709efb6eb5651b78058f19f01a38c", // 用户地址
"to":"0xd14cedc448bfcd8cc3e1b94786573bd6fbd5c661", // 多签合约地址
"gas":"0x83bb",
"gasPrice":"0x1caf4ad00",
"value":"0x38d7ea4c68000",
"data":"0xd46e8dd67c5d32be8d46e8dd67c5d32be8058bb8eb970870f072445675058bb8eb970870f072445675"
}
]
}
跨链交易响应:
{
"jsonrpc":"2.0",
"id":1,
"result":"0xab6fb2d09cd0b7dc44eb4de86ef43ad19fba2c82df2a495e5bb9d33f2e80561f"
}
跨链交易详细信息:
{
"jsonrpc": "2.0",
"id": 1,
"result": {
"blockHash": "0x7e27fee38b0df028f4322e7ebf95d8f47ed0da7733fa1ddbec779d7aaf6fadce",
"blockNumber": "0x1067230",
"chainId": "0x2a",
"condition": null,
"creates": null,
"from": "0x9ba9ae032a2709efb6eb5651b78058f19f01a38c",
"gas": "0x83bb",
"gasPrice": "0x1caf4ad00",
"hash": "0xab6fb2d09cd0b7dc44eb4de86ef43ad19fba2c82df2a495e5bb9d33f2e80561f",
"input": "0x",
"nonce": "0xdb",
"publicKey": "0x465a7b51942e0617debaefbfdd9b31a049a19b9068f54587e3a5e737ab191c5783c350d335be550c2c674df94095aa26e5f3bf6535a4a75255ad7db4b60b2eaa",
"r": "0x29830089f30076d8be18d91bd26afa8044a51f2b32e88533046c54761ddff844",
"raw": "0xf86c81db8501caf4ad008283bb94d14cedc448bfcd8cc3e1b94786573bd6fbd5c66187038d7ea4c680008077a029830089f30076d8be18d91bd26afa8044a51f2b32e88533046c54761ddff844a0509f817bdcf481fecb526fe686e627287cc9860d44fc300dc3a257a0f394cc8a",
"s": "0x509f817bdcf481fecb526fe686e627287cc9860d44fc300dc3a257a0f394cc8a",
"standardV": "0x0",
"to": "0xd14cedc448bfcd8cc3e1b94786573bd6fbd5c661",
"transactionIndex": "0x0",
"v": "0x77",
"value": "0x38d7ea4c68000"
}
}
# 调用注册比原地址合约
注册比原地址合约为Register，继承了Pausable和Ownable，拥有暂停调用和权限控制功能。该合约对外提供了3个函数接口：
- addUser 该函数是供用户注册以太坊地址和比原地址的映射关系
- OwnerChangeRegistry 该函数供合约拥有者修改注册信息
- getVapor 该函数用于查询以太坊地址对应的比原地址
注册比原地址合约源代码如下:
pragma solidity ^0.4.16;
contract Ownable {
address public owner;
/**
* @dev Throws if called by any account other than the owner.
*/
modifier onlyOwner() {
require(msg.sender == owner);
_;
}
/**
* @dev The Ownable constructor sets the original `owner` of the contract to the sender
* account.
*/
function Ownable() public {
owner = msg.sender;
}
/**
* @dev Allows the current owner to transfer control of the contract to a newOwner.
* @param newOwner The address to transfer ownership to.
*/
function transferOwnership(address newOwner) public onlyOwner {
if (newOwner != address(0)) {
owner = newOwner;
}
}
}
contract Pausable is Ownable {
bool public paused = false;
event Pause();
event Unpause();
/**
* @dev Modifier to make a function callable only when the contract is not paused.
*/
modifier whenNotPaused() {
require(!paused);
_;
}
/**
* @dev Modifier to make a function callable only when the contract is paused.
*/
modifier whenPaused() {
require(paused);
_;
}
/**
* @dev called by the owner to pause, triggers stopped state
*/
function pause() onlyOwner whenNotPaused public {
paused = true;
Pause();
}
/**
* @dev called by the owner to unpause, returns to normal state
*/
function unpause() onlyOwner whenPaused public {
paused = false;
Unpause();
}
}
contract Register is Pausable {
// eth 地址 ==> vapor 地址的 map
mapping(address => string) public registry;
// map 中添加新用户, eth 地址为合约调用者,仅未暂停状态下可以调用
function addUser(string vaporAddress) public whenNotPaused {
registry[msg.sender] = vaporAddress;
}
// 合约所有者可以任意更改 map 中的对应关系,仅合约所有者可以调用
function OwnerChangeRegistry(address ethAddress,string vaporAddress) public onlyOwner {
registry[ethAddress] = vaporAddress;
}
//返回 map 中eth 地址对应的 vapor 地址
function getVapor(address ethAddress) public constant returns (string) {
return registry[ethAddress];
}
}
官方开发了一个基于H5开发的以太坊注册比原合约地址的DAPP系统，如果钱包支持H5的嵌入，便可以直接使用（例如imtoken）。此外，钱包还可以根据自己的需求定制该合约的DAPP。