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// Copyright 2011 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// TODO(rsc):
// More precise error handling.
// Presence functionality.
// TODO(mattn):
// Add proxy authentication.
// Package xmpp implements a simple Google Talk client
// using the XMPP protocol described in RFC 3920 and RFC 3921.
package xmpp
import (
"bufio"
"bytes"
"crypto/md5"
"crypto/rand"
"crypto/tls"
"encoding/base64"
"encoding/binary"
"encoding/xml"
"errors"
"fmt"
"io"
"math/big"
"net"
"net/http"
"net/url"
"os"
"strings"
"time"
)
const (
nsStream = "http://etherx.jabber.org/streams"
nsTLS = "urn:ietf:params:xml:ns:xmpp-tls"
nsSASL = "urn:ietf:params:xml:ns:xmpp-sasl"
nsBind = "urn:ietf:params:xml:ns:xmpp-bind"
nsClient = "jabber:client"
nsSession = "urn:ietf:params:xml:ns:xmpp-session"
)
// Default TLS configuration options
var DefaultConfig tls.Config
// Cookie is a unique XMPP session identifier
type Cookie uint64
func getCookie() Cookie {
var buf [8]byte
if _, err := rand.Reader.Read(buf[:]); err != nil {
panic("Failed to read random bytes: " + err.Error())
}
return Cookie(binary.LittleEndian.Uint64(buf[:]))
}
// Client holds XMPP connection opitons
type Client struct {
conn net.Conn // connection to server
jid string // Jabber ID for our connection
domain string
p *xml.Decoder
}
func (c *Client) JID() string {
return c.jid
}
func connect(host, user, passwd string) (net.Conn, error) {
addr := host
if strings.TrimSpace(host) == "" {
a := strings.SplitN(user, "@", 2)
if len(a) == 2 {
addr = a[1]
}
}
a := strings.SplitN(host, ":", 2)
if len(a) == 1 {
addr += ":5222"
}
proxy := os.Getenv("HTTP_PROXY")
if proxy == "" {
proxy = os.Getenv("http_proxy")
}
if proxy != "" {
url, err := url.Parse(proxy)
if err == nil {
addr = url.Host
}
}
c, err := net.Dial("tcp", addr)
if err != nil {
return nil, err
}
if proxy != "" {
fmt.Fprintf(c, "CONNECT %s HTTP/1.1\r\n", host)
fmt.Fprintf(c, "Host: %s\r\n", host)
fmt.Fprintf(c, "\r\n")
br := bufio.NewReader(c)
req, _ := http.NewRequest("CONNECT", host, nil)
resp, err := http.ReadResponse(br, req)
if err != nil {
return nil, err
}
if resp.StatusCode != 200 {
f := strings.SplitN(resp.Status, " ", 2)
return nil, errors.New(f[1])
}
}
return c, nil
}
// Options are used to specify additional options for new clients, such as a Resource.
type Options struct {
// Host specifies what host to connect to, as either "hostname" or "hostname:port"
// If host is not specified, the DNS SRV should be used to find the host from the domainpart of the JID.
// Default the port to 5222.
Host string
// User specifies what user to authenticate to the remote server.
User string
// Password supplies the password to use for authentication with the remote server.
Password string
// Resource specifies an XMPP client resource, like "bot", instead of accepting one
// from the server. Use "" to let the server generate one for your client.
Resource string
// OAuthScope provides go-xmpp the required scope for OAuth2 authentication.
OAuthScope string
// OAuthToken provides go-xmpp with the required OAuth2 token used to authenticate
OAuthToken string
// OAuthXmlNs provides go-xmpp with the required namespaced used for OAuth2 authentication. This is
// provided to the server as the xmlns:auth attribute of the OAuth2 authentication request.
OAuthXmlNs string
// TLS Config
TLSConfig *tls.Config
// InsecureAllowUnencryptedAuth permits authentication over a TCP connection that has not been promoted to
// TLS by STARTTLS; this could leak authentication information over the network, or permit man in the middle
// attacks.
InsecureAllowUnencryptedAuth bool
// NoTLS directs go-xmpp to not use TLS initially to contact the server; instead, a plain old unencrypted
// TCP connection should be used. (Can be combined with StartTLS to support STARTTLS-based servers.)
NoTLS bool
// StartTLS directs go-xmpp to STARTTLS if the server supports it; go-xmpp will automatically STARTTLS
// if the server requires it regardless of this option.
StartTLS bool
// Debug output
Debug bool
// Use server sessions
Session bool
// Presence Status
Status string
// Status message
StatusMessage string
}
// NewClient establishes a new Client connection based on a set of Options.
func (o Options) NewClient() (*Client, error) {
host := o.Host
c, err := connect(host, o.User, o.Password)
if err != nil {
return nil, err
}
if strings.LastIndex(o.Host, ":") > 0 {
host = host[:strings.LastIndex(o.Host, ":")]
}
client := new(Client)
if o.NoTLS {
client.conn = c
} else {
var tlsconn *tls.Conn
if o.TLSConfig != nil {
tlsconn = tls.Client(c, o.TLSConfig)
} else {
DefaultConfig.ServerName = host
tlsconn = tls.Client(c, &DefaultConfig)
}
if err = tlsconn.Handshake(); err != nil {
return nil, err
}
insecureSkipVerify := DefaultConfig.InsecureSkipVerify
if o.TLSConfig != nil {
insecureSkipVerify = o.TLSConfig.InsecureSkipVerify
}
if !insecureSkipVerify {
if err = tlsconn.VerifyHostname(host); err != nil {
return nil, err
}
}
client.conn = tlsconn
}
if err := client.init(&o); err != nil {
client.Close()
return nil, err
}
return client, nil
}
// NewClient creates a new connection to a host given as "hostname" or "hostname:port".
// If host is not specified, the DNS SRV should be used to find the host from the domainpart of the JID.
// Default the port to 5222.
func NewClient(host, user, passwd string, debug bool) (*Client, error) {
opts := Options{
Host: host,
User: user,
Password: passwd,
Debug: debug,
Session: false,
}
return opts.NewClient()
}
// NewClientNoTLS creates a new client without TLS
func NewClientNoTLS(host, user, passwd string, debug bool) (*Client, error) {
opts := Options{
Host: host,
User: user,
Password: passwd,
NoTLS: true,
Debug: debug,
Session: false,
}
return opts.NewClient()
}
// Close closes the XMPP connection
func (c *Client) Close() error {
if c.conn != (*tls.Conn)(nil) {
return c.conn.Close()
}
return nil
}
func saslDigestResponse(username, realm, passwd, nonce, cnonceStr, authenticate, digestURI, nonceCountStr string) string {
h := func(text string) []byte {
h := md5.New()
h.Write([]byte(text))
return h.Sum(nil)
}
hex := func(bytes []byte) string {
return fmt.Sprintf("%x", bytes)
}
kd := func(secret, data string) []byte {
return h(secret + ":" + data)
}
a1 := string(h(username+":"+realm+":"+passwd)) + ":" + nonce + ":" + cnonceStr
a2 := authenticate + ":" + digestURI
response := hex(kd(hex(h(a1)), nonce+":"+nonceCountStr+":"+cnonceStr+":auth:"+hex(h(a2))))
return response
}
func cnonce() string {
randSize := big.NewInt(0)
randSize.Lsh(big.NewInt(1), 64)
cn, err := rand.Int(rand.Reader, randSize)
if err != nil {
return ""
}
return fmt.Sprintf("%016x", cn)
}
func (c *Client) init(o *Options) error {
var domain string
var user string
a := strings.SplitN(o.User, "@", 2)
if len(o.User) > 0 {
if len(a) != 2 {
return errors.New("xmpp: invalid username (want user@domain): " + o.User)
}
user = a[0]
domain = a[1]
} // Otherwise, we'll be attempting ANONYMOUS
// Declare intent to be a jabber client and gather stream features.
f, err := c.startStream(o, domain)
if err != nil {
return err
}
// If the server requires we STARTTLS, attempt to do so.
if f, err = c.startTLSIfRequired(f, o, domain); err != nil {
return err
}
if o.User == "" && o.Password == "" {
foundAnonymous := false
for _, m := range f.Mechanisms.Mechanism {
if m == "ANONYMOUS" {
fmt.Fprintf(c.conn, "<auth xmlns='%s' mechanism='ANONYMOUS' />\n", nsSASL)
foundAnonymous = true
break
}
}
if !foundAnonymous {
return fmt.Errorf("ANONYMOUS authentication is not an option and username and password were not specified")
}
} else {
// Even digest forms of authentication are unsafe if we do not know that the host
// we are talking to is the actual server, and not a man in the middle playing
// proxy.
if !c.IsEncrypted() && !o.InsecureAllowUnencryptedAuth {
return errors.New("refusing to authenticate over unencrypted TCP connection")
}
mechanism := ""
for _, m := range f.Mechanisms.Mechanism {
if m == "X-OAUTH2" && o.OAuthToken != "" && o.OAuthScope != "" {
mechanism = m
// Oauth authentication: send base64-encoded \x00 user \x00 token.
raw := "\x00" + user + "\x00" + o.OAuthToken
enc := make([]byte, base64.StdEncoding.EncodedLen(len(raw)))
base64.StdEncoding.Encode(enc, []byte(raw))
fmt.Fprintf(c.conn, "<auth xmlns='%s' mechanism='X-OAUTH2' auth:service='oauth2' "+
"xmlns:auth='%s'>%s</auth>\n", nsSASL, o.OAuthXmlNs, enc)
break
}
if m == "PLAIN" {
mechanism = m
// Plain authentication: send base64-encoded \x00 user \x00 password.
raw := "\x00" + user + "\x00" + o.Password
enc := make([]byte, base64.StdEncoding.EncodedLen(len(raw)))
base64.StdEncoding.Encode(enc, []byte(raw))
fmt.Fprintf(c.conn, "<auth xmlns='%s' mechanism='PLAIN'>%s</auth>\n", nsSASL, enc)
break
}
if m == "DIGEST-MD5" {
mechanism = m
// Digest-MD5 authentication
fmt.Fprintf(c.conn, "<auth xmlns='%s' mechanism='DIGEST-MD5'/>\n", nsSASL)
var ch saslChallenge
if err = c.p.DecodeElement(&ch, nil); err != nil {
return errors.New("unmarshal <challenge>: " + err.Error())
}
b, err := base64.StdEncoding.DecodeString(string(ch))
if err != nil {
return err
}
tokens := map[string]string{}
for _, token := range strings.Split(string(b), ",") {
kv := strings.SplitN(strings.TrimSpace(token), "=", 2)
if len(kv) == 2 {
if kv[1][0] == '"' && kv[1][len(kv[1])-1] == '"' {
kv[1] = kv[1][1 : len(kv[1])-1]
}
tokens[kv[0]] = kv[1]
}
}
realm, _ := tokens["realm"]
nonce, _ := tokens["nonce"]
qop, _ := tokens["qop"]
charset, _ := tokens["charset"]
cnonceStr := cnonce()
digestURI := "xmpp/" + domain
nonceCount := fmt.Sprintf("%08x", 1)
digest := saslDigestResponse(user, realm, o.Password, nonce, cnonceStr, "AUTHENTICATE", digestURI, nonceCount)
message := "username=\"" + user + "\", realm=\"" + realm + "\", nonce=\"" + nonce + "\", cnonce=\"" + cnonceStr +
"\", nc=" + nonceCount + ", qop=" + qop + ", digest-uri=\"" + digestURI + "\", response=" + digest + ", charset=" + charset
fmt.Fprintf(c.conn, "<response xmlns='%s'>%s</response>\n", nsSASL, base64.StdEncoding.EncodeToString([]byte(message)))
var rspauth saslRspAuth
if err = c.p.DecodeElement(&rspauth, nil); err != nil {
return errors.New("unmarshal <challenge>: " + err.Error())
}
b, err = base64.StdEncoding.DecodeString(string(rspauth))
if err != nil {
return err
}
fmt.Fprintf(c.conn, "<response xmlns='%s'/>\n", nsSASL)
break
}
}
if mechanism == "" {
return fmt.Errorf("PLAIN authentication is not an option: %v", f.Mechanisms.Mechanism)
}
}
// Next message should be either success or failure.
name, val, err := next(c.p)
if err != nil {
return err
}
switch v := val.(type) {
case *saslSuccess:
case *saslFailure:
errorMessage := v.Text
if errorMessage == "" {
// v.Any is type of sub-element in failure,
// which gives a description of what failed if there was no text element
errorMessage = v.Any.Local
}
return errors.New("auth failure: " + errorMessage)
default:
return errors.New("expected <success> or <failure>, got <" + name.Local + "> in " + name.Space)
}
// Now that we're authenticated, we're supposed to start the stream over again.
// Declare intent to be a jabber client.
if f, err = c.startStream(o, domain); err != nil {
return err
}
// Generate a unique cookie
cookie := getCookie()
// Send IQ message asking to bind to the local user name.
if o.Resource == "" {
fmt.Fprintf(c.conn, "<iq type='set' id='%x'><bind xmlns='%s'></bind></iq>\n", cookie, nsBind)
} else {
fmt.Fprintf(c.conn, "<iq type='set' id='%x'><bind xmlns='%s'><resource>%s</resource></bind></iq>\n", cookie, nsBind, o.Resource)
}
var iq clientIQ
if err = c.p.DecodeElement(&iq, nil); err != nil {
return errors.New("unmarshal <iq>: " + err.Error())
}
if &iq.Bind == nil {
return errors.New("<iq> result missing <bind>")
}
c.jid = iq.Bind.Jid // our local id
c.domain = domain
if o.Session {
//if server support session, open it
fmt.Fprintf(c.conn, "<iq to='%s' type='set' id='%x'><session xmlns='%s'/></iq>", xmlEscape(domain), cookie, nsSession)
}
// We're connected and can now receive and send messages.
fmt.Fprintf(c.conn, "<presence xml:lang='en'><show>%s</show><status>%s</status></presence>", o.Status, o.StatusMessage)
return nil
}
// startTlsIfRequired examines the server's stream features and, if STARTTLS is required or supported, performs the TLS handshake.
// f will be updated if the handshake completes, as the new stream's features are typically different from the original.
func (c *Client) startTLSIfRequired(f *streamFeatures, o *Options, domain string) (*streamFeatures, error) {
// whether we start tls is a matter of opinion: the server's and the user's.
switch {
case f.StartTLS == nil:
// the server does not support STARTTLS
return f, nil
case f.StartTLS.Required != nil:
// the server requires STARTTLS.
case !o.StartTLS:
// the user wants STARTTLS and the server supports it.
}
var err error
fmt.Fprintf(c.conn, "<starttls xmlns='urn:ietf:params:xml:ns:xmpp-tls'/>\n")
var k tlsProceed
if err = c.p.DecodeElement(&k, nil); err != nil {
return f, errors.New("unmarshal <proceed>: " + err.Error())
}
tc := o.TLSConfig
if tc == nil {
tc = new(tls.Config)
*tc = DefaultConfig
//TODO(scott): we should consider using the server's address or reverse lookup
tc.ServerName = domain
}
t := tls.Client(c.conn, tc)
if err = t.Handshake(); err != nil {
return f, errors.New("starttls handshake: " + err.Error())
}
c.conn = t
// restart our declaration of XMPP stream intentions.
tf, err := c.startStream(o, domain)
if err != nil {
return f, err
}
return tf, nil
}
// startStream will start a new XML decoder for the connection, signal the start of a stream to the server and verify that the server has
// also started the stream; if o.Debug is true, startStream will tee decoded XML data to stderr. The features advertised by the server
// will be returned.
func (c *Client) startStream(o *Options, domain string) (*streamFeatures, error) {
if o.Debug {
c.p = xml.NewDecoder(tee{c.conn, os.Stderr})
} else {
c.p = xml.NewDecoder(c.conn)
}
_, err := fmt.Fprintf(c.conn, "<?xml version='1.0'?>\n"+
"<stream:stream to='%s' xmlns='%s'\n"+
" xmlns:stream='%s' version='1.0'>\n",
xmlEscape(domain), nsClient, nsStream)
if err != nil {
return nil, err
}
// We expect the server to start a <stream>.
se, err := nextStart(c.p)
if err != nil {
return nil, err
}
if se.Name.Space != nsStream || se.Name.Local != "stream" {
return nil, fmt.Errorf("expected <stream> but got <%v> in %v", se.Name.Local, se.Name.Space)
}
// Now we're in the stream and can use Unmarshal.
// Next message should be <features> to tell us authentication options.
// See section 4.6 in RFC 3920.
f := new(streamFeatures)
if err = c.p.DecodeElement(f, nil); err != nil {
return f, errors.New("unmarshal <features>: " + err.Error())
}
return f, nil
}
// IsEncrypted will return true if the client is connected using a TLS transport, either because it used.
// TLS to connect from the outset, or because it successfully used STARTTLS to promote a TCP connection to TLS.
func (c *Client) IsEncrypted() bool {
_, ok := c.conn.(*tls.Conn)
return ok
}
// Chat is an incoming or outgoing XMPP chat message.
type Chat struct {
Remote string
Type string
Text string
Roster Roster
Other []string
OtherElem []XMLElement
Stamp time.Time
}
type Roster []Contact
type Contact struct {
Remote string
Name string
Group []string
}
// Presence is an XMPP presence notification.
type Presence struct {
From string
To string
Type string
Show string
Status string
}
type IQ struct {
ID string
From string
To string
Type string
Query []byte
}
// Recv waits to receive the next XMPP stanza.
// Return type is either a presence notification or a chat message.
func (c *Client) Recv() (stanza interface{}, err error) {
for {
_, val, err := next(c.p)
if err != nil {
return Chat{}, err
}
switch v := val.(type) {
case *clientMessage:
stamp, _ := time.Parse(
"2006-01-02T15:04:05Z",
v.Delay.Stamp,
)
chat := Chat{
Remote: v.From,
Type: v.Type,
Text: v.Body,
Other: v.OtherStrings(),
OtherElem: v.Other,
Stamp: stamp,
}
return chat, nil
case *clientQuery:
var r Roster
for _, item := range v.Item {
r = append(r, Contact{item.Jid, item.Name, item.Group})
}
return Chat{Type: "roster", Roster: r}, nil
case *clientPresence:
return Presence{v.From, v.To, v.Type, v.Show, v.Status}, nil
case *clientIQ:
if bytes.Equal(v.Query, []byte(`<ping xmlns='urn:xmpp:ping'/>`)) {
err := c.SendResultPing(v.ID, v.From)
if err != nil {
return Chat{}, err
}
}
return IQ{ID: v.ID, From: v.From, To: v.To, Type: v.Type, Query: v.Query}, nil
}
}
}
// Send sends the message wrapped inside an XMPP message stanza body.
func (c *Client) Send(chat Chat) (n int, err error) {
return fmt.Fprintf(c.conn, "<message to='%s' type='%s' xml:lang='en'>"+"<body>%s</body></message>",
xmlEscape(chat.Remote), xmlEscape(chat.Type), xmlEscape(chat.Text))
}
// SendOrg sends the original text without being wrapped in an XMPP message stanza.
func (c *Client) SendOrg(org string) (n int, err error) {
return fmt.Fprint(c.conn, org)
}
func (c *Client) SendPresence(presence Presence) (n int, err error) {
return fmt.Fprintf(c.conn, "<presence from='%s' to='%s'/>", xmlEscape(presence.From), xmlEscape(presence.To))
}
// SendHtml sends the message as HTML as defined by XEP-0071
func (c *Client) SendHtml(chat Chat) (n int, err error) {
return fmt.Fprintf(c.conn, "<message to='%s' type='%s' xml:lang='en'>"+
"<body>%s</body>"+
"<html xmlns='http://jabber.org/protocol/xhtml-im'><body xmlns='http://www.w3.org/1999/xhtml'>%s</body></html></message>",
xmlEscape(chat.Remote), xmlEscape(chat.Type), xmlEscape(chat.Text), chat.Text)
}
// Roster asks for the chat roster.
func (c *Client) Roster() error {
fmt.Fprintf(c.conn, "<iq from='%s' type='get' id='roster1'><query xmlns='jabber:iq:roster'/></iq>\n", xmlEscape(c.jid))
return nil
}
// RFC 3920 C.1 Streams name space
type streamFeatures struct {
XMLName xml.Name `xml:"http://etherx.jabber.org/streams features"`
StartTLS *tlsStartTLS
Mechanisms saslMechanisms
Bind bindBind
Session bool
}
type streamError struct {
XMLName xml.Name `xml:"http://etherx.jabber.org/streams error"`
Any xml.Name
Text string
}
// RFC 3920 C.3 TLS name space
type tlsStartTLS struct {
XMLName xml.Name `xml:"urn:ietf:params:xml:ns:xmpp-tls starttls"`
Required *string `xml:"required"`
}
type tlsProceed struct {
XMLName xml.Name `xml:"urn:ietf:params:xml:ns:xmpp-tls proceed"`
}
type tlsFailure struct {
XMLName xml.Name `xml:"urn:ietf:params:xml:ns:xmpp-tls failure"`
}
// RFC 3920 C.4 SASL name space
type saslMechanisms struct {
XMLName xml.Name `xml:"urn:ietf:params:xml:ns:xmpp-sasl mechanisms"`
Mechanism []string `xml:"mechanism"`
}
type saslAuth struct {
XMLName xml.Name `xml:"urn:ietf:params:xml:ns:xmpp-sasl auth"`
Mechanism string `xml:",attr"`
}
type saslChallenge string
type saslRspAuth string
type saslResponse string
type saslAbort struct {
XMLName xml.Name `xml:"urn:ietf:params:xml:ns:xmpp-sasl abort"`
}
type saslSuccess struct {
XMLName xml.Name `xml:"urn:ietf:params:xml:ns:xmpp-sasl success"`
}
type saslFailure struct {
XMLName xml.Name `xml:"urn:ietf:params:xml:ns:xmpp-sasl failure"`
Any xml.Name `xml:",any"`
Text string `xml:"text"`
}
// RFC 3920 C.5 Resource binding name space
type bindBind struct {
XMLName xml.Name `xml:"urn:ietf:params:xml:ns:xmpp-bind bind"`
Resource string
Jid string `xml:"jid"`
}
// RFC 3921 B.1 jabber:client
type clientMessage struct {
XMLName xml.Name `xml:"jabber:client message"`
From string `xml:"from,attr"`
ID string `xml:"id,attr"`
To string `xml:"to,attr"`
Type string `xml:"type,attr"` // chat, error, groupchat, headline, or normal
// These should technically be []clientText, but string is much more convenient.
Subject string `xml:"subject"`
Body string `xml:"body"`
Thread string `xml:"thread"`
// Any hasn't matched element
Other []XMLElement `xml:",any"`
Delay Delay `xml:"delay"`
}
func (m *clientMessage) OtherStrings() []string {
a := make([]string, len(m.Other))
for i, e := range m.Other {
a[i] = e.String()
}
return a
}
type XMLElement struct {
XMLName xml.Name
InnerXML string `xml:",innerxml"`
}
func (e *XMLElement) String() string {
r := bytes.NewReader([]byte(e.InnerXML))
d := xml.NewDecoder(r)
var buf bytes.Buffer
for {
tok, err := d.Token()
if err != nil {
break
}
switch v := tok.(type) {
case xml.StartElement:
err = d.Skip()
case xml.CharData:
_, err = buf.Write(v)
}
if err != nil {
break
}
}
return buf.String()
}
type Delay struct {
Stamp string `xml:"stamp,attr"`
}
type clientText struct {
Lang string `xml:",attr"`
Body string `xml:"chardata"`
}
type clientPresence struct {
XMLName xml.Name `xml:"jabber:client presence"`
From string `xml:"from,attr"`
ID string `xml:"id,attr"`
To string `xml:"to,attr"`
Type string `xml:"type,attr"` // error, probe, subscribe, subscribed, unavailable, unsubscribe, unsubscribed
Lang string `xml:"lang,attr"`
Show string `xml:"show"` // away, chat, dnd, xa
Status string `xml:"status"` // sb []clientText
Priority string `xml:"priority,attr"`
Error *clientError
}
type clientIQ struct { // info/query
XMLName xml.Name `xml:"jabber:client iq"`
From string `xml:"from,attr"`
ID string `xml:"id,attr"`
To string `xml:"to,attr"`
Type string `xml:"type,attr"` // error, get, result, set
Query []byte `xml:",innerxml"`
Error clientError
Bind bindBind
}
type clientError struct {
XMLName xml.Name `xml:"jabber:client error"`
Code string `xml:",attr"`
Type string `xml:",attr"`
Any xml.Name
Text string
}
type clientQuery struct {
Item []rosterItem
}
type rosterItem struct {
XMLName xml.Name `xml:"jabber:iq:roster item"`
Jid string `xml:",attr"`
Name string `xml:",attr"`
Subscription string `xml:",attr"`
Group []string
}
// Scan XML token stream to find next StartElement.
func nextStart(p *xml.Decoder) (xml.StartElement, error) {
for {
t, err := p.Token()
if err != nil && err != io.EOF || t == nil {
return xml.StartElement{}, err
}
switch t := t.(type) {
case xml.StartElement:
return t, nil
}
}
}
// Scan XML token stream for next element and save into val.
// If val == nil, allocate new element based on proto map.
// Either way, return val.
func next(p *xml.Decoder) (xml.Name, interface{}, error) {
// Read start element to find out what type we want.
se, err := nextStart(p)
if err != nil {
return xml.Name{}, nil, err
}
// Put it in an interface and allocate one.
var nv interface{}
switch se.Name.Space + " " + se.Name.Local {
case nsStream + " features":
nv = &streamFeatures{}
case nsStream + " error":
nv = &streamError{}
case nsTLS + " starttls":
nv = &tlsStartTLS{}
case nsTLS + " proceed":
nv = &tlsProceed{}
case nsTLS + " failure":
nv = &tlsFailure{}
case nsSASL + " mechanisms":
nv = &saslMechanisms{}
case nsSASL + " challenge":
nv = ""
case nsSASL + " response":
nv = ""
case nsSASL + " abort":
nv = &saslAbort{}
case nsSASL + " success":
nv = &saslSuccess{}
case nsSASL + " failure":
nv = &saslFailure{}
case nsBind + " bind":
nv = &bindBind{}
case nsClient + " message":
nv = &clientMessage{}
case nsClient + " presence":
nv = &clientPresence{}
case nsClient + " iq":
nv = &clientIQ{}
case nsClient + " error":
nv = &clientError{}
default:
return xml.Name{}, nil, errors.New("unexpected XMPP message " +
se.Name.Space + " <" + se.Name.Local + "/>")
}
// Unmarshal into that storage.
if err = p.DecodeElement(nv, &se); err != nil {
return xml.Name{}, nil, err
}
return se.Name, nv, err
}
var xmlSpecial = map[byte]string{
'<': "&lt;",
'>': "&gt;",
'"': "&quot;",
'\'': "&apos;",
'&': "&amp;",
}
func xmlEscape(s string) string {
var b bytes.Buffer
for i := 0; i < len(s); i++ {
c := s[i]
if s, ok := xmlSpecial[c]; ok {
b.WriteString(s)
} else {
b.WriteByte(c)
}
}
return b.String()
}
type tee struct {
r io.Reader
w io.Writer
}
func (t tee) Read(p []byte) (n int, err error) {
n, err = t.r.Read(p)
if n > 0 {
t.w.Write(p[0:n])
t.w.Write([]byte("\n"))
}
return
}