From f887d22e3f4d155713455c8cbafd97cadb354312 Mon Sep 17 00:00:00 2001
From: Emir Aganovic <emirfreelance91@gmail.com>
Date: Fri, 2 Jun 2023 22:02:31 +0200
Subject: [PATCH] Doing some final tests. Adding max forward dec handling

---
 client.go                                     | 38 ++++++++++---------
 example/proxysip/main.go                      |  4 ++
 .../proxysip/scripts/clients/pjsua-register   |  4 +-
 parser/parser.go                              |  1 -
 sip/headers.go                                |  8 ++++
 sip/headers_test.go                           |  6 +++
 6 files changed, 40 insertions(+), 21 deletions(-)

diff --git a/client.go b/client.go
index 9a20a4a..a0529a1 100644
--- a/client.go
+++ b/client.go
@@ -1,6 +1,7 @@
 package sipgo
 
 import (
+	"fmt"
 	"net"
 
 	"github.com/emiago/sipgo/sip"
@@ -198,29 +199,32 @@ func ClientRequestAddRecordRoute(c *Client, r *sip.Request) error {
 	return nil
 }
 
-// TODO
 // Based on proxy setup https://www.rfc-editor.org/rfc/rfc3261#section-16
+// ClientRequestDecreaseMaxForward should be used when forwarding request. It decreases max forward
+// in case of 0 it returnes error
 func ClientRequestDecreaseMaxForward(c *Client, r *sip.Request) error {
-	// TODO
+	maxfwd, exists := r.MaxForwards()
+	if !exists {
+		// TODO, should we return error here
+		return nil
+	}
+
+	maxfwd.Dec()
+
+	if maxfwd.Val() <= 0 {
+		return fmt.Errorf("Max forwards reached")
+	}
 	return nil
 }
 
 // ClientResponseRemoveVia is needed when handling client transaction response, where previously used in
 // TransactionRequest with ClientRequestAddVia
 func ClientResponseRemoveVia(c *Client, r *sip.Response) {
-	// via, exists := r.Via()
-	// if !exists {
-	// 	return
-	// }
-	// if via.Host == c.host {
-	// 	r.RemoveHeader("Via")
-	// }
-
-	r.RemoveHeaderOn("Via", c.removeViaCallback)
-}
-
-func (c *Client) removeViaCallback(h sip.Header) bool {
-	// This is slow
-	via := h.(*sip.ViaHeader)
-	return via.Host == c.host
+	via, exists := r.Via()
+	if !exists {
+		return
+	}
+	if via.Host == c.host {
+		r.RemoveHeader("Via")
+	}
 }
diff --git a/example/proxysip/main.go b/example/proxysip/main.go
index 8f59fe6..fb9768c 100644
--- a/example/proxysip/main.go
+++ b/example/proxysip/main.go
@@ -33,6 +33,7 @@ func main() {
 	transportType := flag.String("t", "udp", "Transport, default will be determined by request")
 	flag.Parse()
 
+	transport.UDPMTUSize = 10000
 	if *pprof {
 		runtime.SetBlockProfileRate(1)
 		runtime.SetMutexProfileFraction(1)
@@ -226,6 +227,9 @@ func setupSipProxy(proxydst string, ip string) *sipgo.Server {
 
 	var ackHandler = func(req *sip.Request, tx sip.ServerTransaction) {
 		dst := getDestination(req)
+		if dst == "" {
+			return
+		}
 		req.SetDestination(dst)
 		if err := client.WriteRequest(req, sipgo.ClientRequestAddVia); err != nil {
 			log.Error().Err(err).Msg("Send failed")
diff --git a/example/proxysip/scripts/clients/pjsua-register b/example/proxysip/scripts/clients/pjsua-register
index c7e056f..0124fdb 100755
--- a/example/proxysip/scripts/clients/pjsua-register
+++ b/example/proxysip/scripts/clients/pjsua-register
@@ -7,7 +7,7 @@ if [ "${SIP_USERNAME}" == "" ]; then
   exit 1
 fi
 
-SIP_SERVER_HOST=${SIP_SERVER_HOST:-localhost}
+SIP_SERVER_HOST=${SIP_SERVER_HOST:-127.0.0.1}
 SIP_SERVER_PORT=5060
 SIP_PASSWORD=${SIP_PASSWORD:-asterisk}
 # udp, tcp
@@ -20,11 +20,9 @@ RTP_PORT=$(shuf -i 56001-59999 -n 1)
 
 pjsua \
   --log-level=0 \
-  --app-log-level=0 \
   --no-stderr \
   --null-audio \
   --snd-auto-close=0 \
-  --max-calls=15 \
   --no-vad \
   --use-compact-form \
   --reg-timeout=$SIP_REGISTER_TIMEOUT \
diff --git a/parser/parser.go b/parser/parser.go
index b4e069d..2ae3a66 100644
--- a/parser/parser.go
+++ b/parser/parser.go
@@ -191,7 +191,6 @@ func (p *Parser) parseMsgHeader(msg sip.Message, headerText string) (err error)
 	if !ok {
 		// We have no registered parser for this header type,
 		// so we encapsulate the header data in a GenericHeader struct.
-		// p.log.Tracef("no parser for header type %s", fieldName)
 
 		// TODO Should we check for comma here as well ??
 		header := sip.NewHeader(fieldName, fieldText)
diff --git a/sip/headers.go b/sip/headers.go
index cc04fff..8b1957b 100644
--- a/sip/headers.go
+++ b/sip/headers.go
@@ -714,6 +714,14 @@ func (h *MaxForwardsHeader) Value() string { return strconv.Itoa(int(*h)) }
 
 func (h *MaxForwardsHeader) headerClone() Header { return h }
 
+func (h *MaxForwardsHeader) Dec() {
+	*h = MaxForwardsHeader(uint32(*h) - 1)
+}
+
+func (h MaxForwardsHeader) Val() uint32 {
+	return uint32(h)
+}
+
 // ExpiresHeader is Expires header representation
 type ExpiresHeader uint32
 
diff --git a/sip/headers_test.go b/sip/headers_test.go
index 7ed7a33..88834f9 100644
--- a/sip/headers_test.go
+++ b/sip/headers_test.go
@@ -49,3 +49,9 @@ func BenchmarkHeadersPrepend(b *testing.B) {
 		hs.headerOrder = newOrder
 	})
 }
+
+func TestMaxForwardIncDec(t *testing.T) {
+	maxfwd := MaxForwardsHeader(70)
+	maxfwd.Dec()
+	assert.Equal(t, uint32(69), maxfwd.Val(), "Value returned %d", maxfwd.Val())
+}