<!--
Kamailio Project uses GitHub Issues only for bugs in the code or feature 
requests.

If you have questions about using Kamailio or related to its configuration file,
ask on sr-users mailing list:

  * http://lists.sip-router.org/cgi-bin/mailman/listinfo/sr-users

If you have questions about developing extensions to Kamailio or its existing
C code, ask on sr-dev mailing list

  * http://lists.sip-router.org/cgi-bin/mailman/listinfo/sr-dev

Please try to fill this template as much as possible for any issue. It helps the
developers to troubleshoot the issue.

If you submit a feature request (or enhancement), you can delete the text of
the template and only add the description of what you would like to be added.

If there is no content to be filled in a section, the entire section can be 
removed.

You can delete the comments from the template sections when filling.

You can delete next line and everything above before submitting (it is a 
comment).
-->

### Description

<!--
Explain what you did, what you expected to happen, and what actually happened.
-->

When processing a multipart INVITE using the rtpengine module. The 
rtpengine_offer configuration function (called with default arguments) is 
stripping all bodies except the application/sdp MIME type body.

### Troubleshooting

#### Reproduction

<!--
If the issue can be reproduced, describe how it can be done.
-->

A client is sending an INVITE through a kamailio proxy paired with a rtpengine.

```
Client                                       Proxy                              
         Server
  x        INVITE (SDP)         x                             x                 
            x
  x qqqqqqqqqqqqqqqqqqqqqqqqqq> x                             x                 
            x 
  x         100 Trying          x                             x                 
            x 
  x <qqqqqqqqqqqqqqqqqqqqqqqqqq x                             x                 
            x 
  x                             x                             x        INVITE 
(SDP)         x 
  x                             x                             x 
qqqqqqqqqqqqqqqqqqqqqqqqqq> x 
  x                             x                             x         100 
Trying          x 
  x                             x                             x 
<qqqqqqqqqqqqqqqqqqqqqqqqqq x 
  x                             x                             x                 
            x 
  x                             x                             x                 
            x 
  x                             x                             x                 
            x 
  x                             x                             x                 
            x 
  x                             x                             x                 
            x 
  x                             x                             x                 
            x 
  x                             x                             x        200 OK 
(SDP)         x 
  x                             x                             x 
<qqqqqqqqqqqqqqqqqqqqqqqqqq x 
  x        200 OK (SDP)         x                             x                 
            x 
  x <qqqqqqqqqqqqqqqqqqqqqqqqqq x                             x                 
            x 
```

The INVITE contains a application/sdp body and one or several other bodies of 
different MIME types.

When the INVITE is going out of the proxy, all other bodies except the 
application/sdp MIME are filtered out.

While The INVITE "Content-Type" header is still fixed to : 
`Content-Type: multipart/mixed;boundary="[boundary value]"`

RTP Engine receives only the SDP body on its socket and is rewritting well the 
RTP ports.

#### Debugging Data

<!--
If you got a core dump, use gdb to extract troubleshooting data - full 
backtrace,
local variables and the list of the code at the issue location.

  gdb /path/to/kamailio /path/to/corefile
  bt full
  info locals
  list

If you are familiar with gdb, feel free to attach more of what you consider to
be relevant.
-->

```
(paste your debugging data here)
```

#### Log Messages

<!--
Check the syslog file and if there are relevant log messages printed by 
Kamailio, add them next, or attach to issue, or provide a link to download them 
(e.g., to a pastebin site).
-->

```
(paste your log messages here)
```

#### SIP Traffic

<!--
If the issue is exposed by processing specific SIP messages, grab them with 
ngrep or save in a pcap file, then add them next, or attach to issue, or 
provide a link to download them (e.g., to a pastebin site).
-->

```
(paste your sip traffic here)
```

### Possible Solutions

<!--
If you found a solution or workaround for the issue, describe it. Ideally, 
provide a pull request with a fix.
-->

This issue has been introduced by the following commit : 
36cb753441a78bd13ded119cd468f32623f09fbf.

rtpengine.c :

``` diff
@@ -3328,6 +3328,7 @@ rtpengine_offer_answer(struct sip_msg *msg, const char 
*flags, int op, int more)
        str body, newbody;
        struct lump *anchor;
        pv_value_t pv_val;
 +      str cur_body = {0, 0};
  
        dict = rtpp_function_call_ok(&bencbuf, msg, op, flags, &body);
        if (!dict)
 @@ -3357,7 +3358,12 @@ rtpengine_offer_answer(struct sip_msg *msg, const char 
*flags, int op, int more)
                        pkg_free(newbody.s);
  
                } else {
 -                      anchor = del_lump(msg, body.s - msg->buf, body.len, 0);
 +                      /* get the body from the message as body ptr may have 
changed */
 +                      cur_body.len = 0;
 +                      cur_body.s = get_body(msg);
 +                      cur_body.len = msg->buf + msg->len - cur_body.s;
 +
 +                      anchor = del_lump(msg, cur_body.s - msg->buf, 
cur_body.len, 0);
                        if (!anchor) {
                                LM_ERR("del_lump failed\n");
                                goto error_free;
```
If this commit is removed, the previous behavior is restored.

This commit fixes a segfault: "rtpengine: fixed segfault when using 
read_sdp_pv", so it appears to me that this may be useful.

For, now I am not seeing why this is happening.

### Additional Information

  * **Kamailio Version** - output of `kamailio -v`

seen on: 

```
version: kamailio 5.1.0 (x86_64/linux)
flags: STATS: Off, EXTRA_DEBUG, USE_TCP, USE_TLS, USE_SCTP, TLS_HOOKS, 
DISABLE_NAGLE, USE_MCAST, DNS_IP_HACK, SHM_MEM, 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_BLACKLIST, HAVE_RESOLV_RES
ADAPTIVE_WAIT_LOOPS=1024, MAX_RECV_BUFFER_SIZE 262144, MAX_LISTEN 16, 
MAX_URI_SIZE 1024, BUF_SIZE 65535, DEFAULT PKG_SIZE 8MB
poll method support: poll, epoll_lt, epoll_et, sigio_rt, select.
id: unknown
compiled on 15:29:43 Feb  8 2018 with gcc 4.8.4
```

but I think that the same behavior will be seen on master.

* **Operating System**:

<!--
Details about the operating system, the type: Linux (e.g.,: Debian 8.4, Ubuntu 
16.04, CentOS 7.1, ...), MacOS, xBSD, Solaris, ...;
Kernel details (output of `uname -a`)
-->

```
(paste your output here)
```


-- 
You are receiving this because you are subscribed to this thread.
Reply to this email directly or view it on GitHub:
https://github.com/kamailio/kamailio/issues/1434
_______________________________________________
Kamailio (SER) - Development Mailing List
sr-dev@lists.kamailio.org
https://lists.kamailio.org/cgi-bin/mailman/listinfo/sr-dev

Reply via email to