Re: [Devel] [Users] nathelper/rtpproxy when both SIP UA are behind same NAT

actually, this would be better avp_printf("i:401", "$rd"); if ( avp_check("i:401", "eq/$src_ip/g") ) { xlog("L_INFO", "\"$si\" == \"$rd\" "); } Tavis P wrote: >Opps i made a mistake, instead of "avp_write" you need to use >"avp_printf" to store the pseudo variable into an AVP >and when you are doing the comparison with avp_check you need an alias >defined for the second AVP otherwise you might end up comparing the AVP >with a literal value > > > modparam( "avpops", "avp_aliases", "dest_ip=i:401" ) > > avp_printf("i:400", "$si"); > avp_printf("i:401", "$rd"); > > if ( avp_check("i:400", "eq/$dest_ip/g") ) > { > xlog("L_INFO", "\"$si\" == \"$rd\" "); > } > > >Norman Brandinger wrote: > > > > > > > > >>I agree that the solution that was presented is BAD for the reasons >>stated by both of us and probably more :) >> >>Perhaps using $Ri after the successful lookup() and comparing it to >>the $src_ip AVP would work. >> >>The problem was trying to compare a pseudo variable with an AVP. >> >> >>The doc <snipped below> does not state that pseudo variables can be >>used by avp_write(). >> >>Pseudo-variables can be used with following modules of OpenSER: >> >>* avpops - function “avp_printf()” >>* xlog - functions “xlog()” and “xdbg()” >> >>I did try to use avp_write() to save a pseudo variable to an AVP but >>was unsuccessful. >> >>Do you have an example of writing a pseudo variable to an AVP ? >> >>Regards, >>Norm >> >> >> >>Tavis P wrote: >> >> >> >> >> >> >> >>>Another, more lightweight solution, is: >>> >>>After a successful lookup(location) you can compare the received IP >>>address ($si) with the destination domain/ip address returned from >>>the >>>"lookup" function call ($rd), i think these two pieces of information >>>are reliable for this purpose >>> >>>This way you don't have to make extra database calls to determine >>>locality >>> >>>Also if you want to compare pseudo variables you can first write >>>them to >>>an AVP using "avp_write" and then you can make use of "avp_check" >>>with >>>data sourced from a pseudo variable >>> >>>Norman Brandinger wrote: >>> >>> >>> >>> >>> >>> >>> >>> >>> >>>>I have looked into the problem related to saving saving resources by >>>>not calling rtpproxy or mediaproxy when both the caller and >>>>callee are >>>>behind the same NAT. >>>> >>>>This topic has been discussed many times however, there have been no >>>>"working" examples, or even partial examples posted (that I'm aware >>>>of). >>>> >>>>Below is a solution to the problem, but is a BAD hack at best. >>>> >>>>This solution is BAD because AVP's are added to the usr_preferences >>>>table during the registration process, but there is no notification >>>>that a registration has expired and is no longer valid. A cron job >>>>could be run periodically to delete all received_ip AVP's with no >>>>matching entry in the location table, but this is another hack to >>>>fix >>>>the first hack. >>>> >>>>The solution is BAD because a database calls must be made to save >>>>the >>>>received_ip address into an AVP, then another database call must be >>>>made to reload the value just so that it can be tested against the >>>>caller's $src_ip. A pseudo variable $Ri already exists that >>>>contains >>>>the value we use in received_ip, but I have not been able to find a >>>>way for avp_check() to use $Ri. >>>> >>>>The solution is BAD because it will fail when the SIP device(s) are >>>>behind more than a single NAT router. I believe this is not an >>>>issue >>>>for 95% of the users and 99% of the small office or home users. >>>> >>>>I think that a better solution would be to enhance avp_check() to >>>>accept pseudo variables for the "value" parameter. This would >>>>remove >>>>the need for any database calls. >>>> >>>>I'm cross-posting this response to the developers list to bring this >>>>to their attention and ask for suggestions (it's possible that I've >>>>totally missed something). If a decision is made to open the avpops >>>>module to pseudo variables (other than just avp_print()), I would >>>>suggest the following be looked at: >>>> >>>>avp_check() the value parm should accept pseudo variables >>>>avp_write() the value parm should accept pseudo variables >>>>avp_pushto() the name parameter should accept pseudo variables >>>>avp_op() the value parameter should accept pseudo variables >>>> >>>>Regards, >>>>Norm >>>> >>>> >>>>1) During REGISTER processing, place the following code. I would >>>>suggest that you put the code "after" all authentication checks and >>>>"after" the save("location") statement. >>>> >>>># Delete any previously saved IP addressess from the user. >>>>avp_db_delete("$from/username","s:received_ip"); >>>> >>>># Save the source IP address of the user into an AVP called >>>>received_ip. >>>># The saved IP address should be the public address of the NAT >>>>router. >>>>avp_write("$src_ip", "s:received_ip"); >>>> >>>># Save the AVP received_ip into the usr_preferences tables >>>>associated >>>>with the user that just registered >>>>avp_db_store("$from/username","s:received_ip"); >>>> >>>>2) During INVITE processing (or wherever you make the decision to >>>>use >>>>or not use rtpproxy / mediaproxy) , place the following code. >>>> >>>> >>>>#--------------------------------------------------------------------------- >>>> >>>> >>>> >>>># Are the caller and callee behind the same NAT ? >>>> >>>>#--------------------------------------------------------------------------- >>>> >>>> >>>> >>>>avp_db_load("$to/username", "s:received_ip"); >>>>if (avp_check("s:received_ip", "eq/$src_ip")) { >>>> setflag(CALLER_AND_CALLEE_ ARE_BEHIND_THE_SAME_NAT); >>>>}; >>>> >>>> >>>> >>>>_______________________________________________ >>>>Devel mailing list &gt;&gt;&gt;&gt;Devel(a)openser.org >>>>http://openser.org/cgi-bin/mailman/listinfo/devel >>>> >>>> >>>> >>>> >>>> >>>> >>> >>> >>> >>> >>> >> >> >> >> >> > >_______________________________________________ >Users mailing list &gt;Users(a)openser.org >http://openser.org/cgi-bin/mailman/listinfo/users > > > > > > >