25 Jun
2012
25 Jun
'12
3:44 p.m.
Hi All,
After reading default kamailio configuration i can't understand why does
kamailio remove preloaded route headers from the incoming initial INVITE
before calling record_route().
remove_hf("Route");
if (is_method("INVITE|SUBSCRIBE"))
record_route();
What will happen if an INVITE comes from another SIP proxy which wants
to stay in the middle of the dialogue ?
For example, during Re-INVITE UA from our local site will construct
in-dialog INVITE with R-URI taken from the remote contact and send it to
our local proxy according to RR. Local proxy will process it in
route[WITHNDLG] where loose_route() function will remove top most RR
header because it points to us and since there is no more RR records
forward the request to a destination from the R-URI. As i understand in
that case remote proxy will not receive any in-dialog requests from us.
26 Jun
26 Jun
11:06 a.m.
On 25.06.2012 14:44, Vitaliy Aleksandrov wrote:
Hi All,
After reading default kamailio configuration i can't understand why does
kamailio remove preloaded route headers from the incoming initial INVITE
before calling record_route().
remove_hf("Route");
if (is_method("INVITE|SUBSCRIBE"))
record_route();
Pre-loaded route sets can be used to abuse the proxy as an open relay.
This is bad. If a request hits my proxy, then I want to define how the
message is routed, and I do not want to route the message like somebody
else wants it.
What will happen if an INVITE comes from another SIP proxy which wants
to stay in the middle of the dialogue ?
Only "Route" headers are removed, not "Record-Route" headers which
create the route-set.
For example, during Re-INVITE UA from our local site
will construct
in-dialog INVITE with R-URI taken from the remote contact and send it to
our local proxy according to RR. Local proxy will process it in
route[WITHNDLG] where loose_route() function will remove top most RR
header because it points to us and since there is no more RR records
forward the request to a destination from the R-URI. As i understand in
that case remote proxy will not receive any in-dialog requests from us.
Sure it does. As only the pre-loaded route is remove, not the
Record-Route headers. Thus, the in-dialog route set is not affected,
only the out-of-dialog route set (pre-loaded) is manipulated.
regards
Klaus
4:15 p.m.
New subject: default kamailio configuration.
I have lost in Route and Record-Route headers.
But now it's clear for me. Huge thanks.
On 25.06.2012 14:44, Vitaliy Aleksandrov wrote:
Hi All,
After reading default kamailio configuration i can't understand why does
kamailio remove preloaded route headers from the incoming initial INVITE
before calling record_route().
remove_hf("Route");
if (is_method("INVITE|SUBSCRIBE"))
record_route();
Pre-loaded route sets can be used to abuse the proxy as an open relay.
This is bad. If a request hits my proxy, then I want to define how the
message is routed, and I do not want to route the message like
somebody else wants it.
What will happen if an INVITE comes from another SIP proxy which wants
to stay in the middle of the dialogue ?
Only "Route" headers are removed, not "Record-Route" headers which
create the route-set.
For example, during Re-INVITE UA from our local
site will construct
in-dialog INVITE with R-URI taken from the remote contact and send it to
our local proxy according to RR. Local proxy will process it in
route[WITHNDLG] where loose_route() function will remove top most RR
header because it points to us and since there is no more RR records
forward the request to a destination from the R-URI. As i understand in
that case remote proxy will not receive any in-dialog requests from us.
Sure it does. As only the pre-loaded route is remove, not the
Record-Route headers. Thus, the in-dialog route set is not affected,
only the out-of-dialog route set (pre-loaded) is manipulated.
regards
Klaus
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27 Jun
27 Jun
11:06 a.m.
New subject: default kamailio configuration.
Record-Route is added by proxies to requests creating dialogs to require
that the requests within the dialog will be sent through them. There
Record-Route headers become Route in within dialog requests. In other
words, Route forces next hop address and can be dangerous from security
point of view if not trusted, Record-Route is just to carry some
addresses for later usage, no immediate impact in routing of that request.
Cheers,
Daniel
On 6/26/12 3:15 PM, Vitaliy Aleksandrov wrote:
I have lost in Route and Record-Route headers.
But now it's clear for me. Huge thanks.
--
Daniel-Constantin Mierla - http://www.asipto.com
http://twitter.com/#!/miconda - http://www.linkedin.com/in/miconda
Kamailio Advanced Training, Seattle, USA, Sep 23-26, 2012 - http://asipto.com/u/katu
Kamailio Practical Workshop, Netherlands, Sep 10-12, 2012 - http://asipto.com/u/kpw
On 25.06.2012 14:44, Vitaliy Aleksandrov wrote:
_______________________________________________
SIP Express Router (SER) and Kamailio (OpenSER) - sr-users mailing list
sr-users(a)lists.sip-router.org
http://lists.sip-router.org/cgi-bin/mailman/listinfo/sr-users Hi All,
After reading default kamailio configuration i can't understand why
does
kamailio remove preloaded route headers from the incoming initial
INVITE
before calling record_route().
remove_hf("Route");
if (is_method("INVITE|SUBSCRIBE"))
record_route();
Pre-loaded route sets can be used to abuse the proxy as an open
relay. This is bad. If a request hits my proxy, then I want to define
how the message is routed, and I do not want to route the message
like somebody else wants it.
What will happen if an INVITE comes from another SIP proxy which wants
to stay in the middle of the dialogue ?
Only "Route" headers are removed, not "Record-Route" headers which
create the route-set.
For example, during Re-INVITE UA from our local
site will construct
in-dialog INVITE with R-URI taken from the remote contact and send
it to
our local proxy according to RR. Local proxy will process it in
route[WITHNDLG] where loose_route() function will remove top most RR
header because it points to us and since there is no more RR records
forward the request to a destination from the R-URI. As i
understand in
that case remote proxy will not receive any in-dialog requests from us.
Sure it does. As only the pre-loaded route is remove, not the
Record-Route headers. Thus, the in-dialog route set is not affected,
only the out-of-dialog route set (pre-loaded) is manipulated.
regards
Klaus
_______________________________________________
SIP Express Router (SER) and Kamailio (OpenSER) - sr-users mailing list
sr-users(a)lists.sip-router.org
http://lists.sip-router.org/cgi-bin/mailman/listinfo/sr-users
4531
days inactive
4533
days old
3 comments
3 participants
participants (3)
-
Daniel-Constantin Mierla -
Klaus Darilion -
Vitaliy Aleksandrov