Merge branch 'master' into rework-newlines

go.mod

@@ -0,0 +1,5 @@
+module github.com/mattn/go-xmpp
+
+go 1.20
+
+require golang.org/x/crypto v0.15.0

go.sum

@@ -0,0 +1,2 @@
+golang.org/x/crypto v0.15.0 h1:frVn1TEaCEaZcn3Tmd7Y2b5KKPaZ+I32Q2OA3kYp5TA=
+golang.org/x/crypto v0.15.0/go.mod h1:4ChreQoLWfG3xLDer1WdlH5NdlQ3+mwnQq1YTKY+72g=

xmpp.go

@@ -74,6 +74,7 @@ type Client struct {
 	domain       string
 	p            *xml.Decoder
 	stanzaWriter io.Writer
+	Mechanism    string
 }
 
 func (c *Client) JID() string {
@@ -207,6 +208,9 @@ type Options struct {
 
 	// Status message
 	StatusMessage string
+
+	// Auth mechanism to use
+	Mechanism string
 }
 
 // NewClient establishes a new Client connection based on a set of Options.
@@ -344,7 +348,6 @@ func cnonce() string {
 }
 
 func (c *Client) init(o *Options) error {
-
 	var domain string
 	var user string
 	a := strings.SplitN(o.User, "@", 2)
@@ -372,8 +375,10 @@ func (c *Client) init(o *Options) error {
 	if f, err = c.startTLSIfRequired(f, o, domain); err != nil {
 		return err
 	}
-	var mechanism string
+	var mechanism, channelBinding, clientFirstMessage, clientFinalMessageBare, authMessage string
-	var serverSignature []byte
+	var serverSignature, keyingMaterial []byte
+	var scramPlus, ok, tlsConnOK, tls13 bool
+	var tlsConn *tls.Conn
 	if o.User == "" && o.Password == "" {
 		foundAnonymous := false
 		for _, m := range f.Mechanisms.Mechanism {
@@ -394,17 +399,46 @@ func (c *Client) init(o *Options) error {
 			return errors.New("refusing to authenticate over unencrypted TCP connection")
 		}
 
+		tlsConn, ok = c.conn.(*tls.Conn)
+		if ok {
+			tlsConnOK = true
+		}
 		mechanism = ""
+		if o.Mechanism == "" {
 			for _, m := range f.Mechanisms.Mechanism {
 				switch m {
-			case "SCRAM-SHA-512":
+				case "SCRAM-SHA-512-PLUS":
+					if tlsConnOK {
 						mechanism = m
+					}
+				case "SCRAM-SHA-256-PLUS":
+					if mechanism != "SCRAM-SHA-512-PLUS" && tlsConnOK {
+						mechanism = m
+					}
+				case "SCRAM-SHA-1-PLUS":
+					if mechanism != "SCRAM-SHA-512-PLUS" &&
+						mechanism != "SCRAM-SHA-256-PLUS" &&
+						tlsConnOK {
+						mechanism = m
+					}
+				case "SCRAM-SHA-512":
+					if mechanism != "SCRAM-SHA-512-PLUS" &&
+						mechanism != "SCRAM-SHA-256-PLUS" &&
+						mechanism != "SCRAM-SHA-1-PLUS" {
+						mechanism = m
+					}
 				case "SCRAM-SHA-256":
-				if mechanism != "SCRAM-SHA-512" {
+					if mechanism != "SCRAM-SHA-512-PLUS" &&
+						mechanism != "SCRAM-SHA-256-PLUS" &&
+						mechanism != "SCRAM-SHA-1-PLUS" &&
+						mechanism != "SCRAM-SHA-512" {
 						mechanism = m
 					}
 				case "SCRAM-SHA-1":
-				if mechanism != "SCRAM-SHA-512" &&
+					if mechanism != "SCRAM-SHA-512-PLUS" &&
+						mechanism != "SCRAM-SHA-256-PLUS" &&
+						mechanism != "SCRAM-SHA-1-PLUS" &&
+						mechanism != "SCRAM-SHA-512" &&
 						mechanism != "SCRAM-SHA-256" {
 						mechanism = m
 					}
@@ -422,23 +456,63 @@ func (c *Client) init(o *Options) error {
 					}
 				}
 			}
+		} else {
+			for _, m := range f.Mechanisms.Mechanism {
+				if m == o.Mechanism {
+					mechanism = o.Mechanism
+				}
+			}
+		}
 		if strings.HasPrefix(mechanism, "SCRAM-SHA") {
+			if strings.HasSuffix(mechanism, "PLUS") {
+				scramPlus = true
+			}
+			if scramPlus {
+				tlsState := tlsConn.ConnectionState()
+				switch tlsState.Version {
+				case tls.VersionTLS13:
+					tls13 = true
+					keyingMaterial, err = tlsState.ExportKeyingMaterial("EXPORTER-Channel-Binding", nil, 32)
+					if err != nil {
+						return err
+					}
+				case tls.VersionTLS10, tls.VersionTLS11, tls.VersionTLS12:
+					keyingMaterial = tlsState.TLSUnique
+				default:
+					return errors.New(mechanism + ": unknown TLS version")
+				}
+				if len(keyingMaterial) == 0 {
+					return errors.New(mechanism + ": no keying material")
+				}
+				if tls13 {
+					channelBinding = base64.StdEncoding.EncodeToString(append([]byte("p=tls-exporter,,"), keyingMaterial[:]...))
+				} else {
+					channelBinding = base64.StdEncoding.EncodeToString(append([]byte("p=tls-unique,,"), keyingMaterial[:]...))
+				}
+			}
 			var shaNewFn func() hash.Hash
 			switch mechanism {
-			case "SCRAM-SHA-512":
+			case "SCRAM-SHA-512", "SCRAM-SHA-512-PLUS":
 				shaNewFn = sha512.New
-			case "SCRAM-SHA-256":
+			case "SCRAM-SHA-256", "SCRAM-SHA-256-PLUS":
 				shaNewFn = sha256.New
-			case "SCRAM-SHA-1":
+			case "SCRAM-SHA-1", "SCRAM-SHA-1-PLUS":
 				shaNewFn = sha1.New
 			default:
 				return errors.New("unsupported auth mechanism")
 			}
 			clientNonce := cnonce()
-			clientFirstMessage := "n=" + user + ",r=" + clientNonce
+			if scramPlus {
+				if tls13 {
+					clientFirstMessage = "p=tls-exporter,,n=" + user + ",r=" + clientNonce
+				} else {
+					clientFirstMessage = "p=tls-unique,,n=" + user + ",r=" + clientNonce
+				}
+			} else {
+				clientFirstMessage = "n,,n=" + user + ",r=" + clientNonce
+			}
 			fmt.Fprintf(c.stanzaWriter, "<auth xmlns='%s' mechanism='%s'>%s</auth>\n",
-				nsSASL, mechanism, base64.StdEncoding.EncodeToString([]byte("n,,"+
+				nsSASL, mechanism, base64.StdEncoding.EncodeToString([]byte(clientFirstMessage)))
-					clientFirstMessage)))
 			var sfm string
 			if err = c.p.DecodeElement(&sfm, nil); err != nil {
 				return errors.New("unmarshal <challenge>: " + err.Error())
@@ -469,10 +543,14 @@ func (c *Client) init(o *Options) error {
 						return err
 					}
 				default:
-					return errors.New("unexpected conted in SCRAM challenge")
+					return errors.New("unexpected content in SCRAM challenge")
 				}
 			}
-			clientFinalMessageBare := "c=biws,r=" + serverNonce
+			if scramPlus {
+				clientFinalMessageBare = "c=" + channelBinding + ",r=" + serverNonce
+			} else {
+				clientFinalMessageBare = "c=biws,r=" + serverNonce
+			}
 			saltedPassword := pbkdf2.Key([]byte(o.Password), salt,
 				iterations, shaNewFn().Size(), shaNewFn)
 			h := hmac.New(shaNewFn, saltedPassword)
@@ -484,13 +562,13 @@ func (c *Client) init(o *Options) error {
 			h.Reset()
 			var storedKey []byte
 			switch mechanism {
-			case "SCRAM-SHA-512":
+			case "SCRAM-SHA-512", "SCRAM-SHA-512-PLUS":
 				storedKey512 := sha512.Sum512(clientKey)
 				storedKey = storedKey512[:]
-			case "SCRAM-SHA-256":
+			case "SCRAM-SHA-256", "SCRAM-SH-256-PLUS":
 				storedKey256 := sha256.Sum256(clientKey)
 				storedKey = storedKey256[:]
-			case "SCRAM-SHA-1":
+			case "SCRAM-SHA-1", "SCRAM-SHA-1-PLUS":
 				storedKey1 := sha1.Sum(clientKey)
 				storedKey = storedKey1[:]
 			}
@@ -502,8 +580,8 @@ func (c *Client) init(o *Options) error {
 			if err != nil {
 				return err
 			}
-			authMessage := clientFirstMessage + "," + string(serverFirstMessage) +
+			authMessage = strings.SplitAfter(clientFirstMessage, ",,")[1] + "," +
-				"," + clientFinalMessageBare
+				string(serverFirstMessage) + "," + clientFinalMessageBare
 			h = hmac.New(shaNewFn, storedKey[:])
 			_, err = h.Write([]byte(authMessage))
 			if err != nil {
@@ -625,6 +703,7 @@ func (c *Client) init(o *Options) error {
 			if string(serverSignature) != string(serverSignatureRemote) {
 				return errors.New("SCRAM: server signature mismatch")
 			}
+			c.Mechanism = mechanism
 		}
 	case *saslFailure:
 		errorMessage := v.Text
@@ -892,8 +971,10 @@ func (c *Client) Recv() (stanza interface{}, err error) {
 						return Chat{}, err
 					}
 
-					return IQ{ID: v.ID, From: v.From, To: v.To, Type: v.Type,
+					return IQ{
-						Query: res}, nil
+						ID: v.ID, From: v.From, To: v.To, Type: v.Type,
+						Query: res,
+					}, nil
 				}
 			case v.Type == "result":
 				switch v.ID {
@@ -1021,8 +1102,10 @@ func (c *Client) Recv() (stanza interface{}, err error) {
 						return Chat{}, err
 					}
 
-					return IQ{ID: v.ID, From: v.From, To: v.To, Type: v.Type,
+					return IQ{
-						Query: res}, nil
+						ID: v.ID, From: v.From, To: v.To, Type: v.Type,
+						Query: res,
+					}, nil
 				}
 			case v.Query.XMLName.Local == "":
 				return IQ{ID: v.ID, From: v.From, To: v.To, Type: v.Type}, nil
@@ -1032,8 +1115,10 @@ func (c *Client) Recv() (stanza interface{}, err error) {
 					return Chat{}, err
 				}
 
-				return IQ{ID: v.ID, From: v.From, To: v.To, Type: v.Type,
+				return IQ{
-					Query: res}, nil
+					ID: v.ID, From: v.From, To: v.To, Type: v.Type,
+					Query: res,
+				}, nil
 			}
 		}
 	}
@@ -1112,6 +1197,7 @@ type streamFeatures struct {
 	XMLName        xml.Name `xml:"http://etherx.jabber.org/streams features"`
 	StartTLS       *tlsStartTLS
 	Mechanisms     saslMechanisms
+	ChannelBinding saslChannelBinding
 	Bind           bindBind
 	Session        bool
 }
@@ -1147,6 +1233,16 @@ type saslAuth struct {
 	Mechanism string   `xml:",attr"`
 }
 
+type saslChannelBinding struct {
+	XMLName        xml.Name `xml:"sasl-channel-binding"`
+	Text           string   `xml:",chardata"`
+	Xmlns          string   `xml:"xmlns,attr"`
+	ChannelBinding []struct {
+		Text string `xml:",chardata"`
+		Type string `xml:"type,attr"`
+	} `xml:"channel-binding"`
+}
+
 type saslChallenge string
 
 type saslRspAuth string