func (e *endpoint) ServeNonInvite() {
log.Info("Listening for incoming requests...")
tx := <-e.tm.Requests()
r := tx.Origin()
log.Info("Received request: %v", r.Short())
log.Debug("Full form:\n%v\n", r.String())
// Send a 200 OK
resp := base.NewResponse(
"SIP/2.0",
200,
"OK",
[]base.SipHeader{},
"",
)
base.CopyHeaders("Via", tx.Origin(), resp)
base.CopyHeaders("From", tx.Origin(), resp)
base.CopyHeaders("To", tx.Origin(), resp)
base.CopyHeaders("Call-Id", tx.Origin(), resp)
base.CopyHeaders("CSeq", tx.Origin(), resp)
resp.AddHeader(
&base.ContactHeader{
DisplayName: &e.displayName,
Address: &base.SipUri{
User: &e.username,
Host: e.host,
},
},
)
log.Info("Sending 200 OK")
<-time.After(1 * time.Second)
tx.Respond(resp)
}
// Handle a request.
func (mng *Manager) request(r *base.Request) {
t, ok := mng.getTx(r)
if ok {
t.Receive(r)
return
}
// If we failed to correlate an ACK, just drop it.
if r.Method == base.ACK {
log.Warn("Couldn't correlate ACK to an open transaction. Dropping it.")
return
}
// Create a new transaction
tx := &ServerTransaction{}
tx.tm = mng
tx.origin = r
tx.transport = mng.transport
// Use the remote address in the top Via header. This is not correct behaviour.
viaHeaders := tx.Origin().Headers("Via")
if len(viaHeaders) == 0 {
log.Warn("No Via header on new transaction. Transaction will be dropped.")
return
}
via, ok := viaHeaders[0].(*base.ViaHeader)
if !ok {
panic(errors.New("Headers('Via') returned non-Via header!"))
}
if len(*via) == 0 {
log.Warn("Via header contained no hops! Transaction will be dropped.")
return
}
hop := (*via)[0]
port := uint16(5060)
if hop.Port != nil {
port = *hop.Port
}
tx.dest = fmt.Sprintf("%s:%d", hop.Host, port)
tx.transport = mng.transport
tx.initFSM()
tx.tu = make(chan *base.Response, 3)
tx.tu_err = make(chan error, 1)
tx.ack = make(chan *base.Request, 1)
// Send a 100 Trying immediately.
// Technically we shouldn't do this if we trustthe user to do it within 200ms,
// but I'm not sure how to handle that situation right now.
// Pretend the user sent us a 100 to send.
trying := base.NewResponse(
"SIP/2.0",
100,
"Trying",
[]base.SipHeader{},
"",
)
base.CopyHeaders("Via", tx.origin, trying)
base.CopyHeaders("From", tx.origin, trying)
base.CopyHeaders("To", tx.origin, trying)
base.CopyHeaders("Call-Id", tx.origin, trying)
base.CopyHeaders("CSeq", tx.origin, trying)
tx.lastResp = trying
tx.fsm.Spin(server_input_user_1xx)
mng.requests <- tx
}
// Consume input lines one at a time, producing base.SipMessage objects and sending them down p.output.
func (p *parser) parse(requireContentLength bool) {
var message base.SipMessage
for {
// Parse the StartLine.
startLine, err := p.input.NextLine()
if err != nil {
log.Debug("Parser %p stopped", p)
break
}
if isRequest(startLine) {
method, recipient, sipVersion, err := parseRequestLine(startLine)
message = base.NewRequest(method, recipient, sipVersion, []base.SipHeader{}, "")
p.terminalErr = err
} else if isResponse(startLine) {
sipVersion, statusCode, reason, err := parseStatusLine(startLine)
message = base.NewResponse(sipVersion, statusCode, reason, []base.SipHeader{}, "")
p.terminalErr = err
} else {
p.terminalErr = fmt.Errorf("transmission beginning '%s' is not a SIP message", startLine)
}
if p.terminalErr != nil {
p.terminalErr = fmt.Errorf("failed to parse first line of message: %s", p.terminalErr.Error())
p.errs <- p.terminalErr
break
}
// Parse the header section.
// Headers can be split across lines (marked by whitespace at the start of subsequent lines),
// so store lines into a buffer, and then flush and parse it when we hit the end of the header.
var buffer bytes.Buffer
headers := make([]base.SipHeader, 0)
flushBuffer := func() {
if buffer.Len() > 0 {
newHeaders, err := p.parseHeader(buffer.String())
if err == nil {
headers = append(headers, newHeaders...)
} else {
log.Debug("Skipping header '%s' due to error: %s", buffer.String(), err.Error())
}
buffer.Reset()
}
}
for {
line, err := p.input.NextLine()
if err != nil {
log.Debug("Parser %p stopped", p)
break
}
if len(line) == 0 {
// We've hit the end of the header section.
// Parse anything remaining in the buffer, then break out.
flushBuffer()
break
}
if !strings.Contains(c_ABNF_WS, string(line[0])) {
// This line starts a new header.
// Parse anything currently in the buffer, then store the new header line in the buffer.
flushBuffer()
buffer.WriteString(line)
} else if buffer.Len() > 0 {
// This is a continuation line, so just add it to the buffer.
buffer.WriteString(" ")
buffer.WriteString(line)
} else {
// This is a continuation line, but also the first line of the whole header section.
// Discard it and log.
log.Debug("Discarded unexpected continuation line '%s' at start of header block in message '%s'",
line,
message.Short())
}
}
// Store the headers in the message object.
for _, header := range headers {
message.AddHeader(header)
}
var contentLength int
// Determine the length of the body, so we know when to stop parsing this message.
if p.streamed {
// Use the content-length header to identify the end of the message.
contentLengthHeaders := message.Headers("Content-Length")
if len(contentLengthHeaders) == 0 {
p.terminalErr = fmt.Errorf("Missing required content-length header on message %s", message.Short())
p.errs <- p.terminalErr
break
} else if len(contentLengthHeaders) > 1 {
var errbuf bytes.Buffer
errbuf.WriteString("Multiple content-length headers on message ")
errbuf.WriteString(message.Short())
errbuf.WriteString(":\n")
for _, header := range contentLengthHeaders {
errbuf.WriteString("\t")
errbuf.WriteString(header.String())
}
p.terminalErr = fmt.Errorf(errbuf.String())
p.errs <- p.terminalErr
break
}
contentLength = int(*(contentLengthHeaders[0].(*base.ContentLength)))
} else {
// We're not in streaming mode, so the Write method should have calculated the length of the body for us.
contentLength = (<-p.bodyLengths.Out).(int)
}
// Extract the message body.
body, err := p.input.NextChunk(contentLength)
if err != nil {
log.Debug("Parsed %p stopped", p)
break
}
switch message.(type) {
case *base.Request:
message.(*base.Request).Body = body
case *base.Response:
message.(*base.Response).Body = body
default:
log.Severe("Internal error - message %s is neither a request type nor a response type", message.Short())
}
p.output <- message
}
if !p.streamed {
// We're in unstreamed mode, so we created a bodyLengths ElasticChan which
// needs to be disposed.
close(p.bodyLengths.In)
}
return
}