NOISSUE - Add dtls config to CoAP cli

README.md

@@ -15,11 +15,13 @@ When running, please provide following format:
 | p    | port                                           | "5683"           |
 | d    | data to be sent in POST or PUT                 | ""               |
 | cf   | content format                                 | 50 (JSON format) |
+|tls   | dtls support                                   | false            |
 
+The dtls configuration currently supports PKI certificates. Place the relevant certificates in the certs folder before building.
 ## Examples:
 
 ```bash
-coap-cli get channels/0bb5ba61-a66e-4972-bab6-26f19962678f/messages/subtopic -auth 1e1017e6-dee7-45b4-8a13-00e6afeb66eb -o
+coap-cli get channels/0bb5ba61-a66e-4972-bab6-26f19962678f/messages/subtopic -auth 1e1017e6-dee7-45b4-8a13-00e6afeb66eb -o -tls
 ```
 ```bash
 coap-cli post channels/0bb5ba61-a66e-4972-bab6-26f19962678f/messages/subtopic -auth 1e1017e6-dee7-45b4-8a13-00e6afeb66eb -d "hello world"

cert_utility/utility.go

@@ -0,0 +1,145 @@
+package cert_utility
+
+import (
+	"context"
+	"crypto"
+	"crypto/ecdsa"
+	"crypto/rsa"
+	"crypto/tls"
+	"crypto/x509"
+	"encoding/pem"
+	"errors"
+	"log"
+	"os"
+	"strings"
+
+	piondtls "github.com/pion/dtls/v2"
+)
+
+// Create pion dtls config from certificates.
+func CreateClientConfig(ctx context.Context) (*piondtls.Config, error) {
+	clientKeyBytes := make([]byte, 2048)
+	clientCrtBytes := make([]byte, 2048)
+	caBytes := make([]byte, 2048)
+
+	kb, err := os.Open("../certs/client.key")
+	if err != nil {
+		log.Fatal(err)
+	}
+	defer kb.Close()
+	kb.Read(clientKeyBytes)
+
+	cb, err := os.Open("../certs/client.crt")
+	if err != nil {
+		log.Fatal(err)
+	}
+	defer cb.Close()
+	cb.Read(clientCrtBytes)
+
+	cab, err := os.Open("../certs/ca.crt")
+	if err != nil {
+		log.Fatal(err)
+	}
+	defer cab.Close()
+	cab.Read(caBytes)
+
+	certificate, err := LoadKeyAndCertificate(clientKeyBytes, clientCrtBytes)
+	if err != nil {
+		return nil, err
+	}
+	// cert pool
+	certPool, err := LoadCertPool(caBytes)
+	if err != nil {
+		return nil, err
+	}
+
+	return &piondtls.Config{
+		Certificates:         []tls.Certificate{*certificate},
+		ExtendedMasterSecret: piondtls.RequireExtendedMasterSecret,
+		RootCAs:              certPool,
+		InsecureSkipVerify:   true,
+	}, nil
+}
+
+func LoadCertificate(certBytes []byte) (*tls.Certificate, error) {
+	var certificate tls.Certificate
+
+	for {
+		block, rest := pem.Decode(certBytes)
+		if block == nil {
+			break
+		}
+
+		if block.Type != "CERTIFICATE" {
+			return nil, errors.New("block is not a certificate, unable to load certificates")
+		}
+
+		certificate.Certificate = append(certificate.Certificate, block.Bytes)
+		certBytes = rest
+	}
+
+	if len(certificate.Certificate) == 0 {
+		return nil, errors.New("no certificate found, unable to load certificates")
+	}
+
+	return &certificate, nil
+}
+
+func LoadKey(keyBytes []byte) (crypto.PrivateKey, error) {
+	block, _ := pem.Decode(keyBytes)
+	if block == nil || !strings.HasSuffix(block.Type, "PRIVATE KEY") {
+		return nil, errors.New("block is not a private key, unable to load key")
+	}
+
+	if key, err := x509.ParsePKCS1PrivateKey(block.Bytes); err == nil {
+		return key, nil
+	}
+
+	if key, err := x509.ParsePKCS8PrivateKey(block.Bytes); err == nil {
+		switch key := key.(type) {
+		case *rsa.PrivateKey, *ecdsa.PrivateKey:
+			return key, nil
+		default:
+			return nil, errors.New("unknown key time in PKCS#8 wrapping, unable to load key")
+		}
+	}
+
+	if key, err := x509.ParseECPrivateKey(block.Bytes); err == nil {
+		return key, nil
+	}
+
+	return nil, errors.New("no private key found, unable to load key")
+}
+
+// LoadKeyAndCertificate loads client certificate
+func LoadKeyAndCertificate(keyBytes []byte, certBytes []byte) (*tls.Certificate, error) {
+	certificate, err := LoadCertificate(certBytes)
+	if err != nil {
+		return nil, err
+	}
+	key, err := LoadKey(keyBytes)
+	if err != nil {
+		return nil, err
+	}
+	certificate.PrivateKey = key
+	return certificate, nil
+}
+
+// LoadCertPool loads cert pool from ca certificate
+func LoadCertPool(caBytes []byte) (*x509.CertPool, error) {
+	rootCertificate, err := LoadCertificate(caBytes)
+	if err != nil {
+		return nil, err
+	}
+	certPool := x509.NewCertPool()
+	for _, certBytes := range rootCertificate.Certificate {
+		cert, err := x509.ParseCertificate(certBytes)
+		if err != nil {
+			certPool = nil
+			return nil, err
+		}
+		certPool.AddCert(cert)
+	}
+
+	return certPool, nil
+}

certs/ca.crt

@@ -0,0 +1,3 @@
+-----BEGIN CERTIFICATE-----
+^
+-----END CERTIFICATE-----

certs/client.crt

@@ -0,0 +1,3 @@
+-----BEGIN CERTIFICATE-----
+^
+-----END CERTIFICATE-----

certs/client.key

@@ -0,0 +1,3 @@
+-----BEGIN CERTIFICATE-----
+^
+-----END CERTIFICATE-----

cmd/main.go

@@ -12,10 +12,11 @@ import (
 	"syscall"
 
 	coap "github.com/mainflux/coap-cli/coap"
-	"github.com/plgd-dev/go-coap/v2/message"
-	coapmsg "github.com/plgd-dev/go-coap/v2/message"
-	"github.com/plgd-dev/go-coap/v2/message/codes"
-	"github.com/plgd-dev/go-coap/v2/udp/message/pool"
+
+	"github.com/plgd-dev/go-coap/v3/message"
+	coapmsg "github.com/plgd-dev/go-coap/v3/message"
+	"github.com/plgd-dev/go-coap/v3/message/codes"
+	"github.com/plgd-dev/go-coap/v3/message/pool"
 )
 
 const (
@@ -36,9 +37,10 @@ mathod: get, put, post or delete
 -p      port                                           (default: "5683")
 -d      data to be sent in POST or PUT                 (default: "")
 -cf     content format                                 (default: 50 - JSON format))
-
+-tls   use DTLS                                       (default: false)
+		The current implementation of DTLS uses PKI certificates. Please generate certificates and place them in certs folder.
 Examples:
-coap-cli get channels/0bb5ba61-a66e-4972-bab6-26f19962678f/messages/subtopic -auth 1e1017e6-dee7-45b4-8a13-00e6afeb66eb -o
+coap-cli get channels/0bb5ba61-a66e-4972-bab6-26f19962678f/messages/subtopic -auth 1e1017e6-dee7-45b4-8a13-00e6afeb66eb -o -tls
 coap-cli post channels/0bb5ba61-a66e-4972-bab6-26f19962678f/messages/subtopic -auth 1e1017e6-dee7-45b4-8a13-00e6afeb66eb -d "hello world"
 coap-cli post channels/0bb5ba61-a66e-4972-bab6-26f19962678f/messages/subtopic -auth 1e1017e6-dee7-45b4-8a13-00e6afeb66eb -d "hello world" -h 0.0.0.0 -p 1234
 `
@@ -55,7 +57,7 @@ func parseCode(code string) (codes.Code, error) {
 	case delete:
 		return codes.DELETE, nil
 	}
-	return 0, errors.New("Message can be GET, POST, PUT or DELETE")
+	return 0, errors.New("MESSAGE CAN BE GET, POST, PUT OR DELETE")
 }
 
 func printMsg(m *pool.Message) {
@@ -70,7 +72,7 @@ func main() {
 	}
 	help := strings.ToLower(os.Args[1])
 	if help == "-h" || help == "--help" {
-		log.Println(helpMsg)
+		log.Print(helpMsg)
 		os.Exit(0)
 	}
 
@@ -95,9 +97,10 @@ func main() {
 	cf := flag.Int("cf", 50, "Content format")
 	d := flag.String("d", "", "Message data")
 	a := flag.String("auth", "", "Auth token")
+	s := flag.Bool("tls", false, "Use DTLS")
 	flag.Parse()
 
-	client, err := coap.New(*h + ":" + *p)
+	client, err := coap.New(*h+":"+*p, *s)
 	if err != nil {
 		log.Fatal("Error creating client: ", err)
 	}
@@ -123,9 +126,10 @@ func main() {
 	if err != nil {
 		log.Fatal("Error observing resource: ", err)
 	}
-	errs := make(chan error, 2)
+	errs := make(chan error, 1) // make the channel buffered
+
 	go func() {
-		c := make(chan os.Signal)
+		c := make(chan os.Signal, 1) // make the channel buffered
 		signal.Notify(c, syscall.SIGINT)
 		errs <- fmt.Errorf("%s", <-c)
 	}()

coap/client.go

@@ -8,26 +8,41 @@ import (
 	"log"
 	"time"
 
-	"github.com/plgd-dev/go-coap/v2/message"
-	"github.com/plgd-dev/go-coap/v2/message/codes"
-	"github.com/plgd-dev/go-coap/v2/udp"
-	"github.com/plgd-dev/go-coap/v2/udp/client"
-	"github.com/plgd-dev/go-coap/v2/udp/message/pool"
+	cert_utility "github.com/mainflux/coap-cli/cert_utility"
+
+	"github.com/plgd-dev/go-coap/v3/dtls"
+	"github.com/plgd-dev/go-coap/v3/message"
+	"github.com/plgd-dev/go-coap/v3/message/codes"
+	"github.com/plgd-dev/go-coap/v3/message/pool"
+	"github.com/plgd-dev/go-coap/v3/udp"
+	"github.com/plgd-dev/go-coap/v3/udp/client"
 )
 
 // Client represents CoAP client.
 type Client struct {
-	conn *client.ClientConn
+	conn *client.Conn
 }
 
 // New returns new CoAP client connecting it to the server.
-func New(addr string) (Client, error) {
-	c, err := udp.Dial(addr)
-	if err != nil {
-		log.Fatalf("Error dialing: %v", err)
+func New(addr string, to_dtls bool) (Client, error) {
+	if !to_dtls { // UDP
+		c, err := udp.Dial(addr)
+		if err != nil {
+			log.Fatalf("Error dialing: %v", err)
+		}
+		return Client{conn: c}, nil
+	} else { // DTLS
+		config, err := cert_utility.CreateClientConfig(context.Background())
+		if err != nil {
+			log.Fatalln(err)
+		}
+		co, err := dtls.Dial("localhost:5688", config)
+		if err != nil {
+			log.Fatalf("Error dialing: %v", err)
+		}
+		return Client{conn: co}, err
 	}
 
-	return Client{conn: c}, nil
 }
 
 // Send send a message.
@@ -45,11 +60,14 @@ func (c Client) Send(path string, msgCode codes.Code, cf message.MediaType, payl
 	case codes.DELETE:
 		return c.conn.Delete(ctx, path, opts...)
 	}
-	return nil, errors.New("Invalid message code")
+	return nil, errors.New("INVALID MESSAGE CODE")
 }
 
 // Receive receives a message.
-func (c Client) Receive(path string, opts ...message.Option) (*client.Observation, error) {
+func (c Client) Receive(path string, opts ...message.Option) (interface {
+	Cancel(ctx context.Context, opts ...message.Option) error
+	Canceled() bool
+}, error) {
 	ctx, cancel := context.WithTimeout(context.Background(), time.Minute)
 	defer cancel()
 
@@ -64,4 +82,5 @@ func (c Client) Receive(path string, opts ...message.Option) (*client.Observatio
 			fmt.Println("Payload: ", string(body))
 		}
 	}, opts...)
+
 }

go.mod

@@ -1,12 +1,22 @@
 module github.com/mainflux/coap-cli
 
-go 1.15
+go 1.21
 
 require (
-	github.com/niemeyer/pretty v0.0.0-20200227124842-a10e7caefd8e // indirect
-	github.com/plgd-dev/go-coap/v2 v2.4.0
-	golang.org/x/net v0.0.0-20200513185701-a91f0712d120 // indirect
-	golang.org/x/sys v0.0.0-20201013081832-0aaa2718063a // indirect
-	gopkg.in/check.v1 v1.0.0-20200902074654-038fdea0a05b // indirect
-	gopkg.in/yaml.v2 v2.3.0 // indirect
+	github.com/pion/dtls/v2 v2.2.8-0.20230905141523-2b584af66577
+	github.com/plgd-dev/go-coap/v3 v3.1.5
+)
+
+require (
+	github.com/dsnet/golib/memfile v1.0.0 // indirect
+	github.com/hashicorp/errwrap v1.1.0 // indirect
+	github.com/hashicorp/go-multierror v1.1.1 // indirect
+	github.com/pion/logging v0.2.2 // indirect
+	github.com/pion/transport/v3 v3.0.1 // indirect
+	go.uber.org/atomic v1.11.0 // indirect
+	golang.org/x/crypto v0.13.0 // indirect
+	golang.org/x/exp v0.0.0-20230905200255-921286631fa9 // indirect
+	golang.org/x/net v0.15.0 // indirect
+	golang.org/x/sync v0.3.0 // indirect
+	golang.org/x/sys v0.12.0 // indirect
 )