### Description

When used `rtpengine_manage` function then `RTPengine` node returns the correct response but in the outbound SIP message, SDP is duplicated.

### Troubleshooting

#### Reproduction

Updated /etc/kamailio/kamailio.cfg like in this patch. ```diff diff --git a/etc/kamailio.cfg b/etc/kamailio.cfg index be71dbb54a..89960b38d8 100644 --- a/etc/kamailio.cfg +++ b/etc/kamailio.cfg @@ -1,4 +1,7 @@ #!KAMAILIO +#!define WITH_DEBUG +#!define WITH_NAT +#!define WITH_RTPENGINE # # Kamailio SIP Server v5.5 - default configuration script # - web: https://www.kamailio.org @@ -195,6 +198,8 @@ children=8 * listen=[proto]:[localip]:[lport] advertise [publicip]:[pport] * - it can be set many times to add more sockets to listen to */ # listen=udp:10.0.0.10:5060 +listen=tcp:3.236.25.6:5060 +listen=tcp:[2600:1f18:578:5700::6]:5060

/* life time of TCP connection when there is no traffic * - a bit higher than registration expires to cope with UA behind NAT */ @@ -456,7 +461,7 @@ modparam("presence_xml", "force_active", 1) #!ifdef WITH_NAT #!ifdef WITH_RTPENGINE # ----- rtpengine params ----- -modparam("rtpengine", "rtpengine_sock", "udp:127.0.0.1:2223") +modparam("rtpengine", "rtpengine_sock", "udp6:rtp-us-east-1a-6.nga911.com:2223 udp6:rtp-us-east-1a-7.nga911.com:2223") #!else # ----- rtpproxy params ----- modparam("rtpproxy", "rtpproxy_sock", "udp:127.0.0.1:7722") @@ -528,6 +533,11 @@ request_route { # handle requests within SIP dialogs route(WITHINDLG);

+ if (loose_route()) { + route(NATMANAGE); + record_route(); + route(RELAY); + } ### only initial requests (no To tag)

# authentication @@ -850,10 +860,11 @@ route[NATMANAGE] { if (!(isflagset(FLT_NATS) || isbflagset(FLB_NATB))) return;

#!ifdef WITH_RTPENGINE - if(nat_uac_test("8")) { - rtpengine_manage("SIP-source-address replace-origin replace-session-connection"); + if($avp(rtpengine_offer) == "done") { + rtpengine_manage("ICE=remove address-family=IP4 SDES=off"); } else { - rtpengine_manage("replace-origin replace-session-connection"); + rtpengine_manage("ICE=remove address-family=IP6 SDES=off"); + $avp(rtpengine_offer) = "done"; } #!else if(nat_uac_test("8")) { ``` Make a call via Kamailio node. In my case used a call with "Route" headers.

#### Log Messages

In Kamailio [rtpengine_manage.log](https://github.com/kamailio/kamailio/files/6331086/rtpengine_manage.log), you will find the correct RTPengine response, like: ``` 9(32302) DEBUG: {1 34817407 INVITE 6b2a7c4c-a032-11eb-8c29-870daa274dfe} rtpengine [rtpengine.c:2677]: rtpp_function_call(): proxy reply: d3:sdp599:v=0^M o=2600hz 1618708279 1618708280 IN IP4 192.168.2.10^M s=2600hz^M c=IN IP6 2600:1f18:578:5700::1:e^M t=0 0^M m=audio 16476 RTP/AVP 0 8 102 9 3 103 101 13 104 105^M a=rtpmap:0 PCMU/8000^M a=rtpmap:8 PCMA/8000^M a=rtpmap:102 opus/48000/2^M a=fmtp:102 useinbandfec=1; maxaveragebitrate=30000; maxplaybackrate=48000; ptime=20; minptime=10; maxptime=40^M a=rtpmap:9 G722/8000^M a=rtpmap:3 GSM/8000^M a=rtpmap:103 SPEEX/8000^M a=rtpmap:101 telephone-event/8000^M a=fmtp:101 0-16^M a=rtpmap:13 CN/8000^M a=rtpmap:104 telephone-event/48000^M a=fmtp:104 0-16^M a=rtpmap:105 CN/48000^M a=sendrecv^M a=rtcp:16477^M a=ptime:20^M ``` But SIP message will have duplicated SDP.

#### SIP Traffic

[rtpengine_manage.pcap.gz](https://github.com/kamailio/kamailio/files/6331088/rtpengine_manage.pcap.gz)

### Additional Information

* **Kamailio Version** - output of `kamailio -v` ``` [centos@sbc-a2 ~]$ kamailio -v version: kamailio 5.5.0-pre0 (x86_64/linux) 9413fc flags: USE_TCP, USE_TLS, USE_SCTP, TLS_HOOKS, USE_RAW_SOCKS, DISABLE_NAGLE, USE_MCAST, DNS_IP_HACK, SHM_MMAP, PKG_MALLOC, Q_MALLOC, F_MALLOC, TLSF_MALLOC, DBG_SR_MEMORY, USE_FUTEX, FAST_LOCK-ADAPTIVE_WAIT, USE_DNS_CACHE, USE_DNS_FAILOVER, USE_NAPTR, USE_DST_BLOCKLIST, HAVE_RESOLV_RES, TLS_PTHREAD_MUTEX_SHARED ADAPTIVE_WAIT_LOOPS 1024, MAX_RECV_BUFFER_SIZE 262144, MAX_URI_SIZE 1024, BUF_SIZE 65535, DEFAULT PKG_SIZE 8MB poll method support: poll, epoll_lt, epoll_et, sigio_rt, select. id: 9413fc compiled on 04:03:33 Apr 3 2021 with gcc 8.3.1 ```

* **Operating System**:

``` [centos@sbc-a2 ~]$ cat /etc/os-release NAME="CentOS Linux" VERSION="8" ID="centos" ID_LIKE="rhel fedora" VERSION_ID="8" PLATFORM_ID="platform:el8" PRETTY_NAME="CentOS Linux 8" ANSI_COLOR="0;31" CPE_NAME="cpe:/o:centos:centos:8" HOME_URL="https://centos.org/" BUG_REPORT_URL="https://bugs.centos.org/" CENTOS_MANTISBT_PROJECT="CentOS-8" CENTOS_MANTISBT_PROJECT_VERSION="8" ```