[Linphone-users] bug in SDP on resume from hold

[Daniel Pocock]

I'm testing Linphone against reConServer[1] in Conference mode


When the first user joins, reConServer puts them on hold

When the second user joins, reConServer tells the first user to resume

reConServer sends a re-INVITE to Linphone with a correct SDP offer for IP4:

INVITE sip:daniel@10.1.2.71:5061;transport=udp SIP/2.0
Via: SIP/2.0/UDP
10.1.2.4:5068;branch=z9hG4bK-524287-1---eb6a6d6512e04841;rport
Max-Forwards: 70
Contact: <sip:test@10.1.2.4:5068>
To: "Daniel" <sip:daniel@[2001:....]>;tag=UC35Qmlxe
From: <sip:test@10.1.2.4>;tag=85e07e2d
Call-ID: 47~bZJRCOW
CSeq: 2 INVITE
Session-Expires: 1800;refresher=uac
Min-SE: 90
Accept-Language: en
Allow: INVITE, ACK, CANCEL, OPTIONS, BYE, REFER, NOTIFY, SUBSCRIBE,
UPDATE, PRACK, INFO
Content-Type: application/sdp
Supported: replaces, timer, norefersub, answermode, tdialog
User-Agent: reConServer 1.13.0~alpha1
Content-Length: 239

v=0
o=- 1618481455257285 1618481455257285 IN IP4 10.1.2.4
s=-
c=IN IP4 10.1.2.4
t=0 0
m=audio 17390 RTP/AVP 0 8 97
a=rtpmap:0 PCMU/8000
a=rtpmap:8 PCMA/8000
a=rtpmap:97 telephone-event/8000
a=fmtp:97 0-15
a=ptime:20
a=sendrecv
sigcomp id=


Linphone responds to the re-INVITE with 200 OK.  The SDP is invalid, it
contains the address ::1 (localhost):


SIP/2.0 200 Ok
Via: SIP/2.0/UDP
10.1.2.4:5068;branch=z9hG4bK-524287-1---eb6a6d6512e04841;rport
Contact: "Daniel"
<sip:daniel@10.1.2.71:5061;transport=udp>;+sip.instance="<urn:uuid:d96e3c12-f11a-4d10-b1bd-0b4d86435a83>"
To: "Daniel" <sip:daniel@[2001:....]>;tag=UC35Qmlxe
From: <sip:test@10.1.2.4>;tag=85e07e2d
Call-ID: 47~bZJRCOW
CSeq: 2 INVITE
Allow: INVITE, ACK, CANCEL, OPTIONS, BYE, REFER, NOTIFY, MESSAGE,
SUBSCRIBE, INFO, UPDATE
Content-Type: application/sdp
Supported: replaces, outbound
User-Agent: Linphone/3.12.0 (belle-sip/1.6.3)
Content-Length: 128

v=0
o=daniel 2280 1620 IN IP6 ::1
s=Talk
c=IN IP6 ::1
t=0 0
m=audio 7078 RTP/AVP 0 8 97
a=rtpmap:97 telephone-event/8000



I could work around this by disabling IPv6 in the Linphone settings.
Then it creates a valid SDP answer with a valid IP address.