Send HEP traffic from Kamailio to local sngrep

At the time writing 1.2.0 has not been released. This will only work with compiled sngrep from master branch

This mini tutorial will allow sngrep to receive kamailio packets and can be used to debug received TLS, HEP or SIP packets. HEPv2 support in sngrep is still under testing and this compatibility may or may not work.

Configuring Kamailio to duplicate received packets

• Enable siptrace module in kamailio.cfg

loadmodule    "siptrace.so"

### siptrace ###
modparam("siptrace", "duplicate_uri", "sip:127.0.0.1:9061")
modparam("siptrace", "hep_mode_on", 1)
modparam("siptrace", "trace_to_database", 0)
modparam("siptrace", "trace_flag", 22)
modparam("siptrace", "trace_on", 1)
modparam("siptrace", "hep_version", 2)

• Mark dialogs to be sent with the configured flag

route {
    sip_trace();
    setflag(22);
}

• On Kamailio working as sipcature collector, It should be required to also trace responses. Also, in this kind of Kamailio that doesn't works as proxy, order of messages may not be received in the same order they were originally sent.

onreply_route {
    sip_trace();
}

• Reload your kamailio to apply new configuration

Configuring sngrep to received HEP packets

Previous Kamailio configuration uses HEPv2 to send packets, which is only supported in sngrep since 1.2.0

• Enable HEPv2 en ~/.sngreprc file

set eep.listen on
set eep.listen.version 2
set eep.listen.address 127.0.0.1
set eep.listen.port 9061

If your capagent send CorrelationID enable this option set eep.listen.uuid on

• Run sngrep and you'll see received packets from kamailio