Hi,
I am trying to run the SER as an outbound proxy. Unfortunately
I have some problems. I have used the nathelper/rtpproxy with a customized
ser.conf and the result is that the clients behind NAT are making outbound calls
with no problems. The audio is two-way and all seems best, but when I try to
react a client behind NAT I can not. It is registered in the SIP Proxy, but I
can not dial it.
My scenario is: SER with MySQL authorization on the first PC
and SER with nathelper/rtpproxy for outbound proxy on second PC.
Could someone give me some hint as I can not solve this
problem. The Outbound Proxy SER version is:
version: ser 0.9.3 (i386/linux)
flags: STATS: Off,
USE_IPV6, USE_TCP, DISABLE_NAGLE, USE_MCAST, DNS_IP_HACK, SHM_MEM, SHM_MMAP,
PKG_MALLOC, FAST_LOCK-ADAPTIVE_WAIT
ADAPTIVE_WAIT_LOOPS=1024,
MAX_RECV_BUFFER_SIZE 262144, MAX_LISTEN 16, MAX_URI_SIZE 1024, BUF_SIZE
65535
@(#) $Id: main.c,v 1.197 2004/12/03 19:09:31 andrei Exp $
main.c
compiled on 20:51:59 Jun 28 2005 with gcc 3.3
The ser.cfg of the Outbound Proxy SER is:
#
# $Id: nathelper.cfg,v 1.1 2003/11/10 14:15:36 janakj Exp
$
#
# simple quick-start config script including nathelper
support
# This default script includes nathelper support. To make it
work
# you will also have to install Maxim's RTP proxy. The proxy is
enforced
# if one of the parties is behind a NAT.
#
# If you have an
endpoing in the public internet which is known to
# support symmetric RTP
(Cisco PSTN gateway or voicemail, for example),
# then you don't have to
force RTP proxy. If you don't want to enforce
# RTP proxy for some
destinations than simply use t_relay() instead of
# route(1)
#
#
Sections marked with !! Nathelper contain modifications for nathelper
#
#
NOTE !! This config is EXPERIMENTAL !
#
# ----------- global configuration
parameters ------------------------
debug=3 #
debug level (cmd line: -dddddddddd)
fork=yes
log_stderror=no # (cmd
line: -E)
/* Uncomment these lines to enter debugging
mode
fork=no
log_stderror=yes
*/
check_via=no # (cmd. line:
-v)
dns=no #
(cmd. line: -r)
rev_dns=no # (cmd. line:
-R)
port=5082
children=4
fifo="/tmp/ser_fifo"
# ------------------ module loading
----------------------------------
# Uncomment this if you want to use SQL
database
#loadmodule "/usr/local/lib/ser/modules/mysql.so"
loadmodule "/usr/local/lib/ser/modules/sl.so"
loadmodule
"/usr/local/lib/ser/modules/tm.so"
loadmodule
"/usr/local/lib/ser/modules/rr.so"
loadmodule
"/usr/local/lib/ser/modules/maxfwd.so"
loadmodule
"/usr/local/lib/ser/modules/usrloc.so"
loadmodule
"/usr/local/lib/ser/modules/registrar.so"
loadmodule
"/usr/local/lib/ser/modules/textops.so"
# Uncomment this if you want digest authentication
#
mysql.so must be loaded !
#loadmodule
"/usr/local/lib/ser/modules/auth.so"
#loadmodule
"/usr/local/lib/ser/modules/auth_db.so"
# !! Nathelper
loadmodule
"/usr/local/lib/ser/modules/nathelper.so"
# ----------------- setting module-specific parameters
---------------
# -- usrloc params --
modparam("usrloc", "db_mode", 0)
# Uncomment this if you want to use SQL database
# for
persistent storage and comment the previous line
#modparam("usrloc",
"db_mode", 2)
# -- auth params --
# Uncomment if you are using auth
module
#
#modparam("auth_db", "calculate_ha1", yes)
#
# If you set
"calculate_ha1" parameter to yes (which true in this config),
# uncomment
also the following parameter)
#
#modparam("auth_db", "password_column",
"password")
# -- rr params --
# add value to ;lr param to make some
broken UAs happy
modparam("rr", "enable_full_lr", 1)
# !! Nathelper
modparam("registrar", "nat_flag",
6)
modparam("nathelper", "natping_interval", 60) # Ping interval 60
s
modparam("nathelper", "ping_nated_only", 1) # Ping only clients
behind NAT
# ------------------------- request routing logic
-------------------
# main routing logic
route{
# initial sanity checks -- messages with
#
max_forwards==0, or excessively long requests
if
(!mf_process_maxfwd_header("10")) {
sl_send_reply("483","Too Many
Hops");
break;
};
if (msg:len >=
max_len ) {
sl_send_reply("513", "Message too
big");
break;
};
# !!
Nathelper
# Special handling for NATed clients; first, NAT test
is
# executed: it looks for via!=received and RFC1918
addresses
# in Contact (may fail if line-folding is used);
also,
# the received test should, if completed, should check
all
# vias for rpesence of received
if (nat_uac_test("3"))
{
# Allow RR-ed requests, as these may indicate
that
# a NAT-enabled proxy takes care of it; unless it
is
# a REGISTER
if (method == "REGISTER" || !
search("^Record-Route:")) {
log("LOG: Someone
trying to register from private IP, rewriting\n");
# This will work only for user
agents that support symmetric
# communication.
We tested quite many of them and majority is
#
smart enough to be symmetric. In some phones it takes a
configuration
# option. With Cisco 7960, it is
called NAT_Enable=Yes, with kphone it is
#
called "symmetric media" and "symmetric signalling".
fix_nated_contact(); # Rewrite
contact with source IP of signalling
if
(method == "INVITE") {
fix_nated_sdp("1"); # Add direction=active to
SDP
};
force_rport(); # Add rport parameter to topmost
Via
setflag(6); # Mark as
NATed
};
};
# we record-route all messages -- to make sure
that
# subsequent messages will go through our proxy; that's
#
particularly good if upstream and downstream entities
# use different
transport protocol
if (!method=="REGISTER")
record_route();
# subsequent messages withing a dialog should take
the
# path determined by record-routing
if (loose_route())
{
# mark routing logic in
request
append_hf("P-hint:
rr-enforced\r\n");
route(1);
break;
};
if (!uri==myself) {
# mark routing logic
in request
append_hf("P-hint:
outbound\r\n");
route(1);
break;
};
# if the request is for other domain use
UsrLoc
# (in case, it does not work, use the following
command
# with proper names and addresses in it)
if
(uri==myself) {
if (method=="REGISTER") {
save("location");
break;
};
lookup("aliases");
if
(!uri==myself) {
append_hf("P-hint: outbound
alias\r\n");
route(1);
break;
};
# native SIP destinations are handled using our
USRLOC DB
if (!lookup("location"))
{
sl_send_reply("404", "Not
Found");
break;
};
};
append_hf("P-hint:
usrloc applied\r\n");
route(1);
}
route[1]
{
# !! Nathelper
if
(uri=~"[@:](192\.168\.|10\.|172\.(1[6-9]|2[0-9]|3[0-1])\.)" &&
!search("^Route:")){
sl_send_reply("479", "We don't
forward to private IP addresses");
break;
};
# if client or server know to be behind a NAT, enable
relay
if (isflagset(6)) {
force_rtp_proxy();
};
# NAT processing of replies; apply to all transactions
(for example,
# re-INVITEs from public to private UA are hard to
identify as
# NATed at the moment of request processing); look at
replies
t_on_reply("1");
# send it out now; use stateful forwarding as it works
reliably
# even for UDP2TCP
if (!t_relay())
{
sl_reply_error();
};
}
# !! Nathelper
onreply_route[1] {
#
NATed transaction ?
if (isflagset(6) && status =~
"(183)|2[0-9][0-9]") {
fix_nated_contact();
if (!search("^Content-Length:\ 0"))
{
force_rtp_proxy();
};
#
otherwise, is it a transaction behind a NAT and we did not
# know at time of request processing ? (RFC1918 contacts)
} else if (nat_uac_test("1")) {
fix_nated_contact();
};
}