hermes/backend/commonbackend/marshal.go

417 lines
11 KiB
Go

package commonbackend
import (
"encoding/binary"
"fmt"
"net"
)
func marshalIndividualConnectionStruct(conn *ProxyClientConnection) []byte {
sourceIPOriginal := net.ParseIP(conn.SourceIP)
clientIPOriginal := net.ParseIP(conn.ClientIP)
var serverIPVer uint8
var sourceIP []byte
if sourceIPOriginal.To4() == nil {
serverIPVer = IPv6
sourceIP = sourceIPOriginal.To16()
} else {
serverIPVer = IPv4
sourceIP = sourceIPOriginal.To4()
}
var clientIPVer uint8
var clientIP []byte
if clientIPOriginal.To4() == nil {
clientIPVer = IPv6
clientIP = clientIPOriginal.To16()
} else {
clientIPVer = IPv4
clientIP = clientIPOriginal.To4()
}
connectionBlock := make([]byte, 8+len(sourceIP)+len(clientIP))
connectionBlock[0] = serverIPVer
copy(connectionBlock[1:len(sourceIP)+1], sourceIP)
binary.BigEndian.PutUint16(connectionBlock[1+len(sourceIP):3+len(sourceIP)], conn.SourcePort)
binary.BigEndian.PutUint16(connectionBlock[3+len(sourceIP):5+len(sourceIP)], conn.DestPort)
connectionBlock[5+len(sourceIP)] = clientIPVer
copy(connectionBlock[6+len(sourceIP):6+len(sourceIP)+len(clientIP)], clientIP)
binary.BigEndian.PutUint16(connectionBlock[6+len(sourceIP)+len(clientIP):8+len(sourceIP)+len(clientIP)], conn.ClientPort)
return connectionBlock
}
func marshalIndividualProxyStruct(conn *ProxyInstance) ([]byte, error) {
sourceIPOriginal := net.ParseIP(conn.SourceIP)
var sourceIPVer uint8
var sourceIP []byte
if sourceIPOriginal.To4() == nil {
sourceIPVer = IPv6
sourceIP = sourceIPOriginal.To16()
} else {
sourceIPVer = IPv4
sourceIP = sourceIPOriginal.To4()
}
proxyBlock := make([]byte, 6+len(sourceIP))
proxyBlock[0] = sourceIPVer
copy(proxyBlock[1:len(sourceIP)+1], sourceIP)
binary.BigEndian.PutUint16(proxyBlock[1+len(sourceIP):3+len(sourceIP)], conn.SourcePort)
binary.BigEndian.PutUint16(proxyBlock[3+len(sourceIP):5+len(sourceIP)], conn.DestPort)
var protocolVersion uint8
if conn.Protocol == "tcp" {
protocolVersion = TCP
} else if conn.Protocol == "udp" {
protocolVersion = UDP
} else {
return proxyBlock, fmt.Errorf("invalid protocol recieved")
}
proxyBlock[5+len(sourceIP)] = protocolVersion
return proxyBlock, nil
}
func Marshal(command interface{}) ([]byte, error) {
switch command := command.(type) {
case *Start:
startCommandBytes := make([]byte, 1+2+len(command.Arguments))
startCommandBytes[0] = StartID
binary.BigEndian.PutUint16(startCommandBytes[1:3], uint16(len(command.Arguments)))
copy(startCommandBytes[3:], command.Arguments)
return startCommandBytes, nil
case *Stop:
return []byte{StopID}, nil
case *AddProxy:
sourceIP := net.ParseIP(command.SourceIP)
var ipVer uint8
var ipBytes []byte
if sourceIP.To4() == nil {
ipBytes = sourceIP.To16()
ipVer = IPv6
} else {
ipBytes = sourceIP.To4()
ipVer = IPv4
}
addConnectionBytes := make([]byte, 1+1+len(ipBytes)+2+2+1)
addConnectionBytes[0] = AddProxyID
addConnectionBytes[1] = ipVer
copy(addConnectionBytes[2:2+len(ipBytes)], ipBytes)
binary.BigEndian.PutUint16(addConnectionBytes[2+len(ipBytes):4+len(ipBytes)], command.SourcePort)
binary.BigEndian.PutUint16(addConnectionBytes[4+len(ipBytes):6+len(ipBytes)], command.DestPort)
var protocol uint8
if command.Protocol == "tcp" {
protocol = TCP
} else if command.Protocol == "udp" {
protocol = UDP
} else {
return nil, fmt.Errorf("invalid protocol")
}
addConnectionBytes[6+len(ipBytes)] = protocol
return addConnectionBytes, nil
case *RemoveProxy:
sourceIP := net.ParseIP(command.SourceIP)
var ipVer uint8
var ipBytes []byte
if sourceIP.To4() == nil {
ipBytes = sourceIP.To16()
ipVer = IPv6
} else {
ipBytes = sourceIP.To4()
ipVer = IPv4
}
removeConnectionBytes := make([]byte, 1+1+len(ipBytes)+2+2+1)
removeConnectionBytes[0] = RemoveProxyID
removeConnectionBytes[1] = ipVer
copy(removeConnectionBytes[2:2+len(ipBytes)], ipBytes)
binary.BigEndian.PutUint16(removeConnectionBytes[2+len(ipBytes):4+len(ipBytes)], command.SourcePort)
binary.BigEndian.PutUint16(removeConnectionBytes[4+len(ipBytes):6+len(ipBytes)], command.DestPort)
var protocol uint8
if command.Protocol == "tcp" {
protocol = TCP
} else if command.Protocol == "udp" {
protocol = UDP
} else {
return nil, fmt.Errorf("invalid protocol")
}
removeConnectionBytes[6+len(ipBytes)] = protocol
return removeConnectionBytes, nil
case *ProxyConnectionsResponse:
connectionsArray := make([][]byte, len(command.Connections))
totalSize := 0
for connIndex, conn := range command.Connections {
connectionsArray[connIndex] = marshalIndividualConnectionStruct(conn)
totalSize += len(connectionsArray[connIndex]) + 1
}
if totalSize == 0 {
totalSize = 1
}
connectionCommandArray := make([]byte, totalSize+1)
connectionCommandArray[0] = ProxyConnectionsResponseID
currentPosition := 1
for _, connection := range connectionsArray {
copy(connectionCommandArray[currentPosition:currentPosition+len(connection)], connection)
connectionCommandArray[currentPosition+len(connection)] = '\r'
currentPosition += len(connection) + 1
}
connectionCommandArray[totalSize] = '\n'
return connectionCommandArray, nil
case *CheckClientParameters:
sourceIP := net.ParseIP(command.SourceIP)
var ipVer uint8
var ipBytes []byte
if sourceIP.To4() == nil {
ipBytes = sourceIP.To16()
ipVer = IPv6
} else {
ipBytes = sourceIP.To4()
ipVer = IPv4
}
checkClientBytes := make([]byte, 1+1+len(ipBytes)+2+2+1)
checkClientBytes[0] = CheckClientParametersID
checkClientBytes[1] = ipVer
copy(checkClientBytes[2:2+len(ipBytes)], ipBytes)
binary.BigEndian.PutUint16(checkClientBytes[2+len(ipBytes):4+len(ipBytes)], command.SourcePort)
binary.BigEndian.PutUint16(checkClientBytes[4+len(ipBytes):6+len(ipBytes)], command.DestPort)
var protocol uint8
if command.Protocol == "tcp" {
protocol = TCP
} else if command.Protocol == "udp" {
protocol = UDP
} else {
return nil, fmt.Errorf("invalid protocol")
}
checkClientBytes[6+len(ipBytes)] = protocol
return checkClientBytes, nil
case *CheckServerParameters:
serverCommandBytes := make([]byte, 1+2+len(command.Arguments))
serverCommandBytes[0] = CheckServerParametersID
binary.BigEndian.PutUint16(serverCommandBytes[1:3], uint16(len(command.Arguments)))
copy(serverCommandBytes[3:], command.Arguments)
return serverCommandBytes, nil
case *CheckParametersResponse:
var checkMethod uint8
if command.InResponseTo == "checkClientParameters" {
checkMethod = CheckClientParametersID
} else if command.InResponseTo == "checkServerParameters" {
checkMethod = CheckServerParametersID
} else {
return nil, fmt.Errorf("invalid mode recieved (must be either checkClientParameters or checkServerParameters)")
}
var isValid uint8
if command.IsValid {
isValid = 1
}
checkResponseBytes := make([]byte, 3+2+len(command.Message))
checkResponseBytes[0] = CheckParametersResponseID
checkResponseBytes[1] = checkMethod
checkResponseBytes[2] = isValid
binary.BigEndian.PutUint16(checkResponseBytes[3:5], uint16(len(command.Message)))
if len(command.Message) != 0 {
copy(checkResponseBytes[5:], []byte(command.Message))
}
return checkResponseBytes, nil
case *BackendStatusResponse:
var isRunning uint8
if command.IsRunning {
isRunning = 1
} else {
isRunning = 0
}
statusResponseBytes := make([]byte, 3+2+len(command.Message))
statusResponseBytes[0] = BackendStatusResponseID
statusResponseBytes[1] = isRunning
statusResponseBytes[2] = byte(command.StatusCode)
binary.BigEndian.PutUint16(statusResponseBytes[3:5], uint16(len(command.Message)))
if len(command.Message) != 0 {
copy(statusResponseBytes[5:], []byte(command.Message))
}
return statusResponseBytes, nil
case *BackendStatusRequest:
statusRequestBytes := make([]byte, 1)
statusRequestBytes[0] = BackendStatusRequestID
return statusRequestBytes, nil
case *ProxyStatusRequest:
sourceIP := net.ParseIP(command.SourceIP)
var ipVer uint8
var ipBytes []byte
if sourceIP.To4() == nil {
ipBytes = sourceIP.To16()
ipVer = IPv6
} else {
ipBytes = sourceIP.To4()
ipVer = IPv4
}
commandBytes := make([]byte, 1+1+len(ipBytes)+2+2+1)
commandBytes[0] = ProxyStatusRequestID
commandBytes[1] = ipVer
copy(commandBytes[2:2+len(ipBytes)], ipBytes)
binary.BigEndian.PutUint16(commandBytes[2+len(ipBytes):4+len(ipBytes)], command.SourcePort)
binary.BigEndian.PutUint16(commandBytes[4+len(ipBytes):6+len(ipBytes)], command.DestPort)
var protocol uint8
if command.Protocol == "tcp" {
protocol = TCP
} else if command.Protocol == "udp" {
protocol = UDP
} else {
return nil, fmt.Errorf("invalid protocol")
}
commandBytes[6+len(ipBytes)] = protocol
return commandBytes, nil
case *ProxyStatusResponse:
sourceIP := net.ParseIP(command.SourceIP)
var ipVer uint8
var ipBytes []byte
if sourceIP.To4() == nil {
ipBytes = sourceIP.To16()
ipVer = IPv6
} else {
ipBytes = sourceIP.To4()
ipVer = IPv4
}
commandBytes := make([]byte, 1+1+len(ipBytes)+2+2+1+1)
commandBytes[0] = ProxyStatusResponseID
commandBytes[1] = ipVer
copy(commandBytes[2:2+len(ipBytes)], ipBytes)
binary.BigEndian.PutUint16(commandBytes[2+len(ipBytes):4+len(ipBytes)], command.SourcePort)
binary.BigEndian.PutUint16(commandBytes[4+len(ipBytes):6+len(ipBytes)], command.DestPort)
var protocol uint8
if command.Protocol == "tcp" {
protocol = TCP
} else if command.Protocol == "udp" {
protocol = UDP
} else {
return nil, fmt.Errorf("invalid protocol")
}
commandBytes[6+len(ipBytes)] = protocol
var isActive uint8
if command.IsActive {
isActive = 1
} else {
isActive = 0
}
commandBytes[7+len(ipBytes)] = isActive
return commandBytes, nil
case *ProxyInstanceResponse:
proxyArray := make([][]byte, len(command.Proxies))
totalSize := 0
for proxyIndex, proxy := range command.Proxies {
var err error
proxyArray[proxyIndex], err = marshalIndividualProxyStruct(proxy)
if err != nil {
return nil, err
}
totalSize += len(proxyArray[proxyIndex]) + 1
}
if totalSize == 0 {
totalSize = 1
}
connectionCommandArray := make([]byte, totalSize+1)
connectionCommandArray[0] = ProxyInstanceResponseID
currentPosition := 1
for _, connection := range proxyArray {
copy(connectionCommandArray[currentPosition:currentPosition+len(connection)], connection)
connectionCommandArray[currentPosition+len(connection)] = '\r'
currentPosition += len(connection) + 1
}
connectionCommandArray[totalSize] = '\n'
return connectionCommandArray, nil
case *ProxyInstanceRequest:
return []byte{ProxyInstanceRequestID}, nil
case *ProxyConnectionsRequest:
return []byte{ProxyConnectionsRequestID}, nil
}
return nil, fmt.Errorf("couldn't match command type")
}