package p2p import "github.com/romana/rlog" import "github.com/deroproject/derosuite/globals" import "github.com/deroproject/derosuite/crypto" // when 2 peers communiate either both are in sync or async // if async, reply to the request below, with your state and other will supply you list of block ids // handle BC_NOTIFY_REQUEST_CHAIN func Handle_BC_Notify_Chain(connection *Connection, i_command_header *Levin_Header, buf []byte) { // deserialize data header var i_data_header Levin_Data_Header // incoming data header err := i_data_header.DeSerialize(buf) if err != nil { connection.logger.Debugf("We should destroy connection here, data header cnot deserialized") connection.Exit = true return } buf = i_data_header.Data[11:] // 11 bytes boost header, ignore it // decode remain data length ( though we know it from buffer size, but still verify it ) data_length, done := Decode_Boost_Varint(buf) buf = buf[done:] if data_length == 0 { rlog.Tracef(4, "Peer says it does not have even genesis block, so disconnect") connection.Exit = true return } if (data_length % 32) != 0 { // sanity check rlog.Tracef(4, "We should destroy connection here, packet mismatch") connection.Exit = true return } rlog.Tracef(4, "Number of hashes %d \n", data_length/32) var block_list []crypto.Hash for i := uint64(0); i < data_length/32; i++ { var bhash crypto.Hash copy(bhash[:], buf[i*32:(i+1)*32]) block_list = append(block_list, bhash) rlog.Tracef(5,"%2d hash %x\n", i, bhash[:]) } // the data is like this, first 10 blocks, then block are in 2^n power and the last block is genesis // make sure the genesis block is same if block_list[len(block_list)-1] != globals.Config.Genesis_Block_Hash { connection.logger.Debugf("Peer's genesis block is different from our, so disconnect") connection.Exit = true return } // we must give user our version of the chain start_height := uint64(0) for i := 0; i < len(block_list); i++ { // find the common point in our chain if chain.Block_Exists(block_list[i]) { start_height = chain.Load_Height_for_BL_ID(block_list[i]) rlog.Tracef(4,"Found common point in chain at hash %x\n", block_list[i]) break } } // send atleast 16001 block or till the top stop_height := chain.Get_Height() if (stop_height - start_height) > 1001 { // send MAX 512 KB block hashes stop_height = start_height + 1002 } block_list = block_list[:0] for i := start_height; i < stop_height; i++ { hash, _ := chain.Load_BL_ID_at_Height(i) block_list = append(block_list, hash) } rlog.Tracef(2,"Prepared list of %d block header to send \n", len(block_list)) Send_BC_Notify_Response_Chain_Entry(connection, block_list, start_height, chain.Get_Height(), 1) } // header from boost packet //0060 00 00 00 01 11 01 01 01 01 02 01 [] 01 04 09 62 6c ..............bl //0070 6f 63 6b 5f 69 64 73 0a [] 81 0a 9b a2 3e fe 50 5f ock_ids.....>.P_ // send the Peer our chain status, so he can give us the latest chain or updated block_ids // this is only sent when we are in different from peers func Send_BC_Notify_Chain_Command(connection *Connection) { connection.Lock() header_bytes := []byte{ /*0x01, 0x04,*/ 0x09, 0x62, 0x6c, 0x6f, 0x63, 0x6b, 0x5f, 0x69, 0x64, 0x73, 0x0a} _ = header_bytes // now append boost variant length, and then append all the hashes var block_list []crypto.Hash // add your blocks here our_height := chain.Get_Height() if our_height < 20 { // if height is less than 20, fetch from genesis block } else { // send blocks in reverse for i := uint64(1); our_height < 11; i++ { hash, err := chain.Load_BL_ID_at_Height(our_height - i) _ = err block_list = append(block_list, hash) } our_height = our_height - 11 // now seend all our block id in log, 2nd, 4th, 8th, etc for ; our_height > 0; our_height = our_height >> 1 { hash, err := chain.Load_BL_ID_at_Height(our_height) _ = err block_list = append(block_list, hash) } } // final block is always genesis block block_list = append(block_list, globals.Config.Genesis_Block_Hash) buf := make([]byte, 8, 8) done := Encode_Boost_Varint(buf, uint64(len(block_list)*32)) // encode length of buffer buf = buf[:done] var o_command_header Levin_Header var o_data_header Levin_Data_Header o_data_header.Data = append(header_bytes, buf...) // convert and append all hashes to bytes for _, hash := range block_list { o_data_header.Data = append(o_data_header.Data, hash[:32]...) } o_data_bytes, _ := o_data_header.Serialize() o_data_bytes[9] = 0x4 o_command_header.CB = uint64(len(o_data_bytes)) o_command_header.Command = BC_NOTIFY_REQUEST_CHAIN o_command_header.ReturnData = false o_command_header.Flags = LEVIN_PACKET_REQUEST o_command_header_bytes, _ := o_command_header.Serialize() connection.Conn.Write(o_command_header_bytes) connection.Conn.Write(o_data_bytes) //fmt.Printf("len of command header %d\n", len(o_command_header_bytes)) //fmt.Printf("len of data header %d\n", len(o_data_bytes)) connection.Unlock() }