Add modbus proxy

cmd/config.go

@@ -18,6 +18,7 @@ import (
 	"github.com/evcc-io/evcc/server"
 	autoauth "github.com/evcc-io/evcc/server/auth"
 	"github.com/evcc-io/evcc/util"
+	"github.com/evcc-io/evcc/util/modbus"
 	"github.com/evcc-io/evcc/vehicle"
 	"github.com/evcc-io/evcc/vehicle/wrapper"
 	"github.com/gorilla/handlers"
@@ -47,13 +48,14 @@ type config struct {
 	Network      networkConfig
 	Log          string
 	SponsorToken string
-	Telemetry    bool
 	Plant        string // telemetry plant id
+	Telemetry    bool
 	Metrics      bool
 	Profile      bool
 	Levels       map[string]string
 	Interval     time.Duration
 	Mqtt         mqttConfig
+	ModbusProxy  []proxyConfig
 	Database     dbConfig
 	Javascript   map[string]interface{}
 	Influx       server.InfluxConfig
@@ -73,6 +75,12 @@ type mqttConfig struct {
 	Topic       string
 }
 
+type proxyConfig struct {
+	Port            int
+	ReadOnly        bool
+	modbus.Settings `mapstructure:",squash"`
+}
+
 type dbConfig struct {
 	Type string
 	Dsn  string

cmd/setup.go

@@ -20,6 +20,7 @@ import (
 	"github.com/evcc-io/evcc/server"
 	"github.com/evcc-io/evcc/server/db"
 	"github.com/evcc-io/evcc/server/db/settings"
+	"github.com/evcc-io/evcc/server/modbus"
 	"github.com/evcc-io/evcc/tariff"
 	"github.com/evcc-io/evcc/util"
 	"github.com/evcc-io/evcc/util/locale"
@@ -106,6 +107,15 @@ func configureEnvironment(cmd *cobra.Command, conf config) (err error) {
 		err = configureMQTT(conf.Mqtt)
 	}
 
+	// setup modbus proxy listeners
+	if err == nil {
+		for _, cfg := range conf.ModbusProxy {
+			if err = modbus.StartProxy(cfg.Port, cfg.Settings, cfg.ReadOnly); err != nil {
+				break
+			}
+		}
+	}
+
 	// setup javascript VMs
 	if err == nil {
 		err = configureJavascript(conf.Javascript)

evcc.dist.yaml

@@ -37,6 +37,14 @@ levels:
   cache: error
   db: error
 
+# modbus proxy for allowing external programs to reuse the evcc modbus connection
+# each entry will start a proxy instance at the given port speaking Modbus TCP and
+# relaying to the given modbus downstream device (either TCP or RTU, RS485 or TCP)
+modbusproxy:
+  #  - port: 5200
+  #    uri: localhost:502
+  #    readonly: true
+
 # meter definitions
 # name can be freely chosen and is used as reference when assigning meters to site and loadpoints
 # for documentation see https://docs.evcc.io/docs/devices/meters

go.mod

@@ -8,6 +8,7 @@ require (
 	github.com/Masterminds/sprig/v3 v3.2.2
 	github.com/PuerkitoBio/goquery v1.8.0
 	github.com/andig/gosunspec v0.0.0-20211108155140-af2e73b86e71
+	github.com/andig/mbserver v0.0.0-20221101145037-fcaa2dfef9fb
 	github.com/asaskevich/EventBus v0.0.0-20200907212545-49d423059eef
 	github.com/avast/retry-go/v3 v3.1.1
 	github.com/aws/aws-sdk-go v1.44.127

go.sum

@@ -98,6 +98,8 @@ github.com/andig/go-powerwall v0.2.1-0.20220205120646-e5220ad9a9a0 h1:9fQ/afZNwq
 github.com/andig/go-powerwall v0.2.1-0.20220205120646-e5220ad9a9a0/go.mod h1:NA12RXBKXFQFx3Nb9xMTQjHIphu1Fl64i/gQMuRdMZc=
 github.com/andig/gosunspec v0.0.0-20211108155140-af2e73b86e71 h1:tnjVNZjuz+CK6fdc7ohJpMHjcEGFI5APp0l5T5Ocr/Y=
 github.com/andig/gosunspec v0.0.0-20211108155140-af2e73b86e71/go.mod h1:c6P6szcR+ROkqZruOR4f6qbDKFjZX6OitPpj+yJ/r8k=
+github.com/andig/mbserver v0.0.0-20221101145037-fcaa2dfef9fb h1:cw8kFzV0kbG4E4Bv4UOmbgNkhCEZ0p7frNCFO4LKzm0=
+github.com/andig/mbserver v0.0.0-20221101145037-fcaa2dfef9fb/go.mod h1:4VtYzTm//oUipwvO3yh0g/udTE7pYJM+U/kyAuFDsgM=
 github.com/andig/rct v0.0.0-20221101081802-96d01efdc68c h1:iXNLsesR2rTRPmr+QbjGgRTAOue8QpIkibakicNR7Qg=
 github.com/andig/rct v0.0.0-20221101081802-96d01efdc68c/go.mod h1:0lfd2mmBnBzIvuzYtdhG+2371u+cUfIxsYErm4P9KRI=
 github.com/andybalholm/cascadia v1.2.0/go.mod h1:YCyR8vOZT9aZ1CHEd8ap0gMVm2aFgxBp0T0eFw1RUQY=
@@ -292,6 +294,7 @@ github.com/go-stack/stack v1.8.0/go.mod h1:v0f6uXyyMGvRgIKkXu+yp6POWl0qKG85gN/me
 github.com/go-task/slim-sprig v0.0.0-20210107165309-348f09dbbbc0/go.mod h1:fyg7847qk6SyHyPtNmDHnmrv/HOrqktSC+C9fM+CJOE=
 github.com/go-telegram-bot-api/telegram-bot-api/v5 v5.5.1 h1:wG8n/XJQ07TmjbITcGiUaOtXxdrINDz1b0J1w0SzqDc=
 github.com/go-telegram-bot-api/telegram-bot-api/v5 v5.5.1/go.mod h1:A2S0CWkNylc2phvKXWBBdD3K0iGnDBGbzRpISP2zBl8=
+github.com/goburrow/serial v0.1.0 h1:v2T1SQa/dlUqQiYIT8+Cu7YolfqAi3K96UmhwYyuSrA=
 github.com/gobwas/httphead v0.0.0-20180130184737-2c6c146eadee h1:s+21KNqlpePfkah2I+gwHF8xmJWRjooY+5248k6m4A0=
 github.com/gobwas/httphead v0.0.0-20180130184737-2c6c146eadee/go.mod h1:L0fX3K22YWvt/FAX9NnzrNzcI4wNYi9Yku4O0LKYflo=
 github.com/gobwas/pool v0.2.0 h1:QEmUOlnSjWtnpRGHF3SauEiOsy82Cup83Vf2LcMlnc8=
@@ -774,6 +777,7 @@ github.com/shopspring/decimal v1.3.1/go.mod h1:DKyhrW/HYNuLGql+MJL6WCR6knT2jwCFR
 github.com/shurcooL/graphql v0.0.0-20220606043923-3cf50f8a0a29 h1:B1PEwpArrNp4dkQrfxh/abbBAOZBVp0ds+fBEOUOqOc=
 github.com/shurcooL/graphql v0.0.0-20220606043923-3cf50f8a0a29/go.mod h1:AuYgA5Kyo4c7HfUmvRGs/6rGlMMV/6B1bVnB9JxJEEg=
 github.com/shurcooL/sanitized_anchor_name v1.0.0/go.mod h1:1NzhyTcUVG4SuEtjjoZeVRXNmyL/1OwPU0+IJeTBvfc=
+github.com/simonvetter/modbus v1.6.0 h1:RDHJevtc7LDIVoHAbhDun8fy+QwnGe+ZU+sLm9ZZzjc=
 github.com/sirupsen/logrus v1.2.0/go.mod h1:LxeOpSwHxABJmUn/MG1IvRgCAasNZTLOkJPxbbu5VWo=
 github.com/sirupsen/logrus v1.4.2/go.mod h1:tLMulIdttU9McNUspp0xgXVQah82FyeX6MwdIuYE2rE=
 github.com/sirupsen/logrus v1.6.0/go.mod h1:7uNnSEd1DgxDLC74fIahvMZmmYsHGZGEOFrfsX/uA88=

server/modbus/handler.go

@@ -0,0 +1,141 @@
+package modbus
+
+import (
+	"encoding/binary"
+	"errors"
+
+	"github.com/andig/mbserver"
+	"github.com/evcc-io/evcc/util"
+	"github.com/evcc-io/evcc/util/modbus"
+	gridx "github.com/grid-x/modbus"
+)
+
+type handler struct {
+	log      *util.Logger
+	readOnly bool
+	mbserver.RequestHandler
+	conn *modbus.Connection
+}
+
+func bytesAsUint16(b []byte) []uint16 {
+	u := make([]uint16, 0, len(b)/2)
+	for i := 0; i < len(b)/2; i++ {
+		u = append(u, binary.BigEndian.Uint16(b[2*i:]))
+	}
+	return u
+}
+
+func asBytes(u []uint16) []byte {
+	b := make([]byte, 2*len(u))
+	for i, u := range u {
+		binary.BigEndian.PutUint16(b[2*i:], u)
+	}
+	return b
+}
+
+func bytesAsBool(b []byte) []bool {
+	var res []bool
+	for _, c := range bytesAsUint16(b) {
+		if c != 0 {
+			res = append(res, true)
+			continue
+		}
+		res = append(res, false)
+	}
+	return res
+}
+
+func boolAsBytes(b []bool) []byte {
+	res := make([]byte, 2*len(b))
+	for i, bb := range b {
+		if bb {
+			binary.BigEndian.PutUint16(res[2*i:], 0xFF00)
+		}
+	}
+	return res
+}
+
+func (h *handler) logResult(op string, b []byte, err error) {
+	if err == nil {
+		h.log.TRACE.Printf(op+" response: %0x", b)
+	} else {
+		h.log.TRACE.Printf(op+" response: %v", err)
+	}
+}
+
+func (h *handler) exceptionToUint16AndError(op string, b []byte, err error) ([]uint16, error) {
+	h.logResult(op, b, err)
+
+	var modbusError *gridx.Error
+	if errors.As(err, &modbusError) {
+		err = mbserver.MapExceptionCodeToError(modbusError.ExceptionCode)
+	}
+
+	return bytesAsUint16(b), err
+}
+
+func (h *handler) exceptionToBoolAndError(op string, b []byte, err error) ([]bool, error) {
+	h.logResult(op, b, err)
+
+	var modbusError *gridx.Error
+	if errors.As(err, &modbusError) {
+		err = mbserver.MapExceptionCodeToError(modbusError.ExceptionCode)
+	}
+
+	return bytesAsBool(b), err
+}
+
+func (h *handler) HandleCoils(req *mbserver.CoilsRequest) ([]bool, error) {
+	if req.IsWrite {
+		if h.readOnly {
+			return nil, mbserver.ErrIllegalFunction
+		}
+
+		if req.Quantity == 1 {
+			h.log.TRACE.Printf("write coil: id: %d addr: %d val: %t", req.UnitId, req.Addr, req.Args[0])
+			var u uint16
+			if req.Args[0] {
+				u = 0xFF00
+			}
+
+			b, err := h.conn.WriteSingleCoilWithSlave(req.UnitId, req.Addr, u)
+			return h.exceptionToBoolAndError("write coil", b, err)
+		}
+
+		h.log.TRACE.Printf("write multiple coils: id: %d addr: %d qty: %d val: %v", req.UnitId, req.Addr, req.Quantity, req.Args)
+		b, err := h.conn.WriteMultipleCoilsWithSlave(req.UnitId, req.Addr, req.Quantity, boolAsBytes(req.Args))
+		return h.exceptionToBoolAndError("write multiple coils", b, err)
+	}
+
+	h.log.TRACE.Printf("read coil: id: %d addr: %d qty: %d", req.UnitId, req.Addr, req.Quantity)
+	b, err := h.conn.ReadCoilsWithSlave(req.UnitId, req.Addr, req.Quantity)
+	return h.exceptionToBoolAndError("read coil", b, err)
+}
+
+func (h *handler) HandleInputRegisters(req *mbserver.InputRegistersRequest) (res []uint16, err error) {
+	h.log.TRACE.Printf("read input: id: %d addr: %d qty: %d", req.UnitId, req.Addr, req.Quantity)
+	b, err := h.conn.ReadInputRegistersWithSlave(req.UnitId, req.Addr, req.Quantity)
+	return h.exceptionToUint16AndError("read input", b, err)
+}
+
+func (h *handler) HandleHoldingRegisters(req *mbserver.HoldingRegistersRequest) (res []uint16, err error) {
+	if req.IsWrite {
+		if h.readOnly {
+			return nil, mbserver.ErrIllegalFunction
+		}
+
+		if req.Quantity == 1 {
+			h.log.TRACE.Printf("write holding: id: %d addr: %d val: %0x", req.UnitId, req.Addr, req.Args[0])
+			b, err := h.conn.WriteSingleRegisterWithSlave(req.UnitId, req.Addr, req.Args[0])
+			return h.exceptionToUint16AndError("write holding", b, err)
+		}
+
+		h.log.TRACE.Printf("write multiple holding: id: %d addr: %d qty: %d val: %0x", req.UnitId, req.Addr, req.Quantity, asBytes(req.Args))
+		b, err := h.conn.WriteMultipleRegistersWithSlave(req.UnitId, req.Addr, req.Quantity, asBytes(req.Args))
+		return h.exceptionToUint16AndError("write multiple holding", b, err)
+	}
+
+	h.log.TRACE.Printf("read holding: id: %d addr: %d qty: %d", req.UnitId, req.Addr, req.Quantity)
+	b, err := h.conn.ReadHoldingRegistersWithSlave(req.UnitId, req.Addr, req.Quantity)
+	return h.exceptionToUint16AndError("read holding", b, err)
+}

server/modbus/proxy.go

@@ -0,0 +1,45 @@
+package modbus
+
+import (
+	"fmt"
+	"net"
+
+	"github.com/andig/mbserver"
+	"github.com/evcc-io/evcc/api"
+	"github.com/evcc-io/evcc/util"
+	"github.com/evcc-io/evcc/util/modbus"
+	"github.com/evcc-io/evcc/util/sponsor"
+)
+
+func StartProxy(port int, config modbus.Settings, readOnly bool) error {
+	conn, err := modbus.NewConnection(config.URI, config.Device, config.Comset, config.Baudrate, modbus.ProtocolFromRTU(config.RTU), config.ID)
+	if err != nil {
+		return err
+	}
+
+	if !sponsor.IsAuthorized() {
+		return api.ErrSponsorRequired
+	}
+
+	h := &handler{
+		log:            util.NewLogger(fmt.Sprintf("proxy-%d", port)),
+		readOnly:       readOnly,
+		RequestHandler: new(mbserver.DummyHandler),
+		conn:           conn,
+	}
+
+	l, err := net.Listen("tcp", fmt.Sprintf(":%d", port))
+	if err != nil {
+		return err
+	}
+
+	h.log.DEBUG.Printf("modbus proxy for %s listening at :%d", config.String(), port)
+
+	srv, err := mbserver.New(h)
+
+	if err == nil {
+		err = srv.Start(l)
+	}
+
+	return err
+}

server/modbus/proxy_test.go

@@ -0,0 +1,70 @@
+package modbus
+
+import (
+	"encoding/binary"
+	"math/rand"
+	"net"
+	"sync"
+	"testing"
+	"time"
+
+	"github.com/andig/mbserver"
+	"github.com/evcc-io/evcc/util/modbus"
+	"github.com/stretchr/testify/assert"
+)
+
+func TestProxyRead(t *testing.T) {
+	l, err := net.Listen("tcp", ":0")
+	assert.NoError(t, err)
+	defer l.Close()
+
+	t.Log(l.Addr().String())
+
+	conn, err := modbus.NewConnection(l.Addr().String(), "", "", 0, modbus.Tcp, 1)
+	assert.NoError(t, err)
+
+	h := &echoHandler{
+		id:             0,
+		RequestHandler: new(mbserver.DummyHandler),
+		conn:           conn,
+	}
+
+	srv, _ := mbserver.New(h)
+	assert.NoError(t, srv.Start(l))
+	defer func() { _ = srv.Stop() }()
+
+	var wg sync.WaitGroup
+
+	for i := 1; i <= 10; i++ {
+		wg.Add(1)
+
+		go func(id int) {
+			for i := 0; i < 50; i++ {
+				addr := uint16(rand.Int31n(200) + 1)
+
+				b, err := conn.ReadInputRegistersWithSlave(uint8(id), addr, 1)
+				assert.NoError(t, err)
+
+				if err == nil {
+					assert.Equal(t, addr^uint16(id), binary.BigEndian.Uint16(b))
+				}
+
+				time.Sleep(time.Duration(rand.Int31n(1000)) * time.Microsecond)
+			}
+
+			wg.Done()
+		}(i)
+	}
+
+	wg.Wait()
+}
+
+type echoHandler struct {
+	id int
+	mbserver.RequestHandler
+	conn *modbus.Connection
+}
+
+func (h *echoHandler) HandleInputRegisters(req *mbserver.InputRegistersRequest) (res []uint16, err error) {
+	return []uint16{req.Addr ^ uint16(req.UnitId)}, err
+}